diff --git a/.changeset/six-adapter-initial.md b/.changeset/six-adapter-initial.md
new file mode 100644
index 00000000000..1ac27105127
--- /dev/null
+++ b/.changeset/six-adapter-initial.md
@@ -0,0 +1,5 @@
+---
+'@chainlink/six-adapter': major
+---
+
+New adapter for SIX Exchange and BME equity market data via WebSocket streaming with mTLS authentication
diff --git a/.pnp.cjs b/.pnp.cjs
index a51709666f1..e7648ac6595 100644
--- a/.pnp.cjs
+++ b/.pnp.cjs
@@ -618,6 +618,10 @@ const RAW_RUNTIME_STATE =
       "name": "@chainlink/securitize-adapter",\
       "reference": "workspace:packages/sources/securitize"\
     },\
+    {\
+      "name": "@chainlink/six-adapter",\
+      "reference": "workspace:packages/sources/six"\
+    },\
     {\
       "name": "@chainlink/snowflake-adapter",\
       "reference": "workspace:packages/sources/snowflake"\
@@ -931,6 +935,7 @@ const RAW_RUNTIME_STATE =
     ["@chainlink/secure-mint-adapter", ["workspace:packages/composites/secure-mint"]],\
     ["@chainlink/securitize-adapter", ["workspace:packages/sources/securitize"]],\
     ["@chainlink/set-token-index-adapter", ["workspace:packages/composites/set-token-index"]],\
+    ["@chainlink/six-adapter", ["workspace:packages/sources/six"]],\
     ["@chainlink/snowflake-adapter", ["workspace:packages/sources/snowflake"]],\
     ["@chainlink/sochain-adapter", ["workspace:packages/sources/sochain"]],\
     ["@chainlink/solactive-adapter", ["workspace:packages/sources/solactive"]],\
@@ -7583,6 +7588,26 @@ const RAW_RUNTIME_STATE =
         "linkType": "SOFT"\
       }]\
     ]],\
+    ["@chainlink/six-adapter", [\
+      ["workspace:packages/sources/six", {\
+        "packageLocation": "./packages/sources/six/",\
+        "packageDependencies": [\
+          ["@chainlink/six-adapter", "workspace:packages/sources/six"],\
+          ["@chainlink/external-adapter-framework", "npm:2.13.1"],\
+          ["@sinonjs/fake-timers", "npm:9.1.2"],\
+          ["@types/jest", "npm:29.5.14"],\
+          ["@types/node", "npm:22.14.1"],\
+          ["@types/sinonjs__fake-timers", "npm:8.1.5"],\
+          ["@types/ws", "npm:8.18.1"],\
+          ["axios", "npm:1.13.4"],\
+          ["nock", "npm:13.5.6"],\
+          ["tslib", "npm:2.4.1"],\
+          ["typescript", "patch:typescript@npm%3A5.8.3#optional!builtin<compat/typescript>::version=5.8.3&hash=5786d5"],\
+          ["ws", "virtual:76798ef4297c06624e6a890a042a8db65fa32cc5d1d7d8828006e188fc8f070b35b00d18d56a03211a6f7ef7c28f126042b0f4ef3fc99489849fd25a37aa15d0#npm:8.18.3"]\
+        ],\
+        "linkType": "SOFT"\
+      }]\
+    ]],\
     ["@chainlink/snowflake-adapter", [\
       ["workspace:packages/sources/snowflake", {\
         "packageLocation": "./packages/sources/snowflake/",\
diff --git a/packages/sources/six/package.json b/packages/sources/six/package.json
new file mode 100644
index 00000000000..88b8eeec86b
--- /dev/null
+++ b/packages/sources/six/package.json
@@ -0,0 +1,45 @@
+{
+  "name": "@chainlink/six-adapter",
+  "version": "0.1.0",
+  "description": "Chainlink six adapter.",
+  "keywords": [
+    "Chainlink",
+    "LINK",
+    "blockchain",
+    "oracle",
+    "six"
+  ],
+  "main": "dist/index.js",
+  "types": "dist/index.d.ts",
+  "files": [
+    "dist"
+  ],
+  "repository": {
+    "url": "https://github.com/smartcontractkit/external-adapters-js",
+    "type": "git"
+  },
+  "license": "MIT",
+  "scripts": {
+    "clean": "rm -rf dist && rm -f tsconfig.tsbuildinfo",
+    "prepack": "yarn build",
+    "build": "tsc -b",
+    "server": "node -e 'require(\"./index.js\").server()'",
+    "server:dist": "node -e 'require(\"./dist/index.js\").server()'",
+    "start": "yarn server:dist"
+  },
+  "devDependencies": {
+    "@sinonjs/fake-timers": "9.1.2",
+    "@types/jest": "^29.5.14",
+    "@types/node": "22.14.1",
+    "@types/sinonjs__fake-timers": "8.1.5",
+    "@types/ws": "^8",
+    "nock": "13.5.6",
+    "typescript": "5.8.3"
+  },
+  "dependencies": {
+    "@chainlink/external-adapter-framework": "2.13.1",
+    "axios": "1.13.4",
+    "tslib": "2.4.1",
+    "ws": "^8.18.3"
+  }
+}
diff --git a/packages/sources/six/src/config/index.ts b/packages/sources/six/src/config/index.ts
new file mode 100644
index 00000000000..fed5e61a69d
--- /dev/null
+++ b/packages/sources/six/src/config/index.ts
@@ -0,0 +1,32 @@
+import { AdapterConfig } from '@chainlink/external-adapter-framework/config'
+
+export const config = new AdapterConfig(
+  {
+    WS_API_ENDPOINT: {
+      description: 'SIX WebSocket API endpoint',
+      type: 'string',
+      default: 'wss://api.six-group.com/web/v2/websocket',
+      required: true,
+      sensitive: false,
+    },
+    REST_API_ENDPOINT: {
+      description: 'SIX REST API base URL (used to fetch Market Base reference data)',
+      type: 'string',
+      default: 'https://api.six-group.com',
+      required: true,
+      sensitive: false,
+    },
+    CONFLATION_PERIOD: {
+      description: 'Conflation period in ISO 8601 duration format (e.g. PT1S for 1 second)',
+      type: 'string',
+      default: 'PT1S',
+      required: false,
+      sensitive: false,
+    },
+  },
+  {
+    envDefaultOverrides: {
+      CACHE_MAX_AGE: 10_000, // 10s - data updates every 1s, stale after 10s
+    },
+  },
+)
diff --git a/packages/sources/six/src/endpoint/price.ts b/packages/sources/six/src/endpoint/price.ts
new file mode 100644
index 00000000000..127c194a5ac
--- /dev/null
+++ b/packages/sources/six/src/endpoint/price.ts
@@ -0,0 +1,58 @@
+import { AdapterEndpoint } from '@chainlink/external-adapter-framework/adapter/endpoint'
+import { InputParameters } from '@chainlink/external-adapter-framework/validation'
+import { config } from '../config'
+import { generateTransport } from '../transport/price'
+
+const inputParameters = new InputParameters(
+  {
+    ticker: {
+      aliases: ['base', 'symbol', 'asset'],
+      required: true,
+      type: 'string',
+      description: 'Instrument ticker (e.g. ABBN, ALC, ANA, ANE)',
+    },
+    bc: {
+      aliases: ['market', 'bourseCode', 'exchange'],
+      required: true,
+      type: 'string',
+      description: 'SIX Bourse Code (e.g. 4 for SIX Swiss Exchange, 1058 for BME)',
+    },
+  },
+  [
+    {
+      ticker: 'ABBN',
+      bc: '4',
+    },
+  ],
+)
+
+interface PriceResponse {
+  Result: number | null
+  Data: {
+    mid?: number
+    bid?: number
+    bidSize?: number
+    ask?: number
+    askSize?: number
+    lastTradedPrice?: number
+    volume?: number
+    marketStatus: number
+    ripcord: boolean
+    ripcordAsInt: number
+  }
+}
+
+export type BaseEndpointTypes = {
+  Parameters: typeof inputParameters.definition
+  Response: PriceResponse
+  Settings: typeof config.settings
+}
+
+const transport = generateTransport()
+
+export const endpoint = new AdapterEndpoint({
+  name: 'price',
+  aliases: ['equity', 'stock'],
+  transport,
+  inputParameters,
+})
diff --git a/packages/sources/six/src/index.ts b/packages/sources/six/src/index.ts
new file mode 100644
index 00000000000..5f7d7d4b06d
--- /dev/null
+++ b/packages/sources/six/src/index.ts
@@ -0,0 +1,13 @@
+import { expose, ServerInstance } from '@chainlink/external-adapter-framework'
+import { Adapter } from '@chainlink/external-adapter-framework/adapter'
+import { config } from './config'
+import { endpoint } from './endpoint/price'
+
+export const adapter = new Adapter({
+  defaultEndpoint: endpoint.name,
+  name: 'SIX',
+  config,
+  endpoints: [endpoint],
+})
+
+export const server = (): Promise<ServerInstance | undefined> => expose(adapter)
diff --git a/packages/sources/six/src/transport/price.ts b/packages/sources/six/src/transport/price.ts
new file mode 100644
index 00000000000..37fecc1f9c3
--- /dev/null
+++ b/packages/sources/six/src/transport/price.ts
@@ -0,0 +1,273 @@
+import { WebSocketTransport } from '@chainlink/external-adapter-framework/transports/websocket'
+import { makeLogger, ProviderResult } from '@chainlink/external-adapter-framework/util'
+import axios from 'axios'
+import https from 'https'
+import { BaseEndpointTypes } from '../endpoint/price'
+import {
+  buildCloseStreamQuery,
+  buildSubscriptionQuery,
+  mapMarketBaseStatusToV11,
+  MARKET_STATUS_UNKNOWN,
+  toMilliseconds,
+} from './utils'
+
+const logger = makeLogger('SixPriceTransport')
+
+const STALE_DATA_THRESHOLD_SECONDS = 300
+const MARKET_BASE_REQUEST_TIMEOUT_MS = 10_000
+
+type SixPriceField = {
+  value?: number
+  size?: number
+  unixTimestamp?: number
+}
+
+type SixStreamMessage = {
+  type: 'START' | 'UPDATE' | 'STOP' | 'ERROR'
+  requestedId: string
+  streamId: string
+  requestedScheme: string
+  last?: SixPriceField
+  bestBid?: SixPriceField
+  bestAsk?: SixPriceField
+  mid?: SixPriceField
+  volume?: SixPriceField
+}
+
+type WsMessage = {
+  data?: {
+    startStream?: SixStreamMessage[]
+  }
+  errors?: { message: string; category?: string; type?: string; messageCode?: number }[]
+}
+
+type MarketBaseMarket = {
+  lookupStatus?: string
+  referenceData?: {
+    marketBase?: {
+      marketStatus?: string
+    }
+  }
+}
+
+type MarketBaseResponse = {
+  data?: {
+    markets?: MarketBaseMarket[]
+  }
+}
+
+export type WsTransportTypes = BaseEndpointTypes & {
+  Provider: {
+    WsMessage: WsMessage
+  }
+}
+
+// Market Base `marketStatus` is quasi-static (exchange-level flag, not session
+// state). Cache per BC for the process lifetime; on the first message for a
+// new BC we kick off an async fetch and return MARKET_STATUS_UNKNOWN until the
+// cache is populated.
+const marketStatusByBc = new Map<string, number>()
+const pendingMarketStatusFetches = new Set<string>()
+
+let cachedCredentials: { cert: Buffer; key: Buffer } | undefined
+let cachedHttpsAgent: https.Agent | undefined
+
+const getCredentials = (certBase64: string, keyBase64: string) => {
+  if (!cachedCredentials) {
+    cachedCredentials = {
+      cert: Buffer.from(certBase64, 'base64'),
+      key: Buffer.from(keyBase64, 'base64'),
+    }
+  }
+  return cachedCredentials
+}
+
+const getHttpsAgent = (): https.Agent | undefined => {
+  if (!cachedCredentials) return undefined
+  if (!cachedHttpsAgent) {
+    cachedHttpsAgent = new https.Agent({
+      cert: cachedCredentials.cert,
+      key: cachedCredentials.key,
+    })
+  }
+  return cachedHttpsAgent
+}
+
+const fetchMarketBaseStatus = async (bc: string, restEndpoint: string): Promise<number> => {
+  const httpsAgent = getHttpsAgent()
+  if (!httpsAgent) throw new Error('mTLS credentials not initialized')
+  const response = await axios.get<MarketBaseResponse>(
+    `${restEndpoint}/web/v2/markets/referenceData/marketBase`,
+    {
+      params: { scheme: 'BC', ids: bc },
+      headers: { accept: 'application/json' },
+      httpsAgent,
+      timeout: MARKET_BASE_REQUEST_TIMEOUT_MS,
+    },
+  )
+  const status = response.data.data?.markets?.[0]?.referenceData?.marketBase?.marketStatus
+  return mapMarketBaseStatusToV11(status)
+}
+
+const ensureMarketStatusFetched = (bc: string, restEndpoint: string): void => {
+  if (marketStatusByBc.has(bc) || pendingMarketStatusFetches.has(bc)) return
+  if (!cachedCredentials) return
+  pendingMarketStatusFetches.add(bc)
+  fetchMarketBaseStatus(bc, restEndpoint)
+    .then((status) => {
+      marketStatusByBc.set(bc, status)
+      logger.info({ bc, status }, 'Market base status fetched')
+    })
+    .catch((error) => {
+      logger.error({ bc, error: String(error) }, 'Failed to fetch market base status')
+    })
+    .finally(() => {
+      pendingMarketStatusFetches.delete(bc)
+    })
+}
+
+const makeRipcordResult = (
+  ticker: string,
+  bc: string,
+  details: string,
+): ProviderResult<WsTransportTypes> => ({
+  params: { ticker, bc },
+  response: {
+    statusCode: 502,
+    errorMessage: `Ripcord activated for ${ticker}_${bc}. Details: ${details}`,
+  },
+})
+
+export const generateTransport = () => {
+  const transport = new WebSocketTransport<WsTransportTypes>({
+    url: ({ adapterSettings: { WS_API_ENDPOINT } }) => WS_API_ENDPOINT,
+
+    options: ({ adapterSettings: { TLS_PUBLIC_KEY, TLS_PRIVATE_KEY } }) => {
+      if (!TLS_PUBLIC_KEY || !TLS_PRIVATE_KEY) {
+        throw new Error('TLS_PUBLIC_KEY and TLS_PRIVATE_KEY must be set (Base64-encoded)')
+      }
+      const { cert, key } = getCredentials(TLS_PUBLIC_KEY, TLS_PRIVATE_KEY)
+      return { cert, key }
+    },
+
+    handlers: {
+      open: async () => {
+        logger.info('Connected to SIX WebSocket API')
+      },
+
+      message: (message, context): ProviderResult<WsTransportTypes>[] | undefined => {
+        if (message.errors) {
+          logger.error({ errors: message.errors }, 'SIX API returned errors')
+          return []
+        }
+
+        const streams = message.data?.startStream
+        if (!streams) return []
+
+        const results: ProviderResult<WsTransportTypes>[] = []
+
+        for (const stream of streams) {
+          const parts = stream.streamId.split('_')
+          if (parts.length !== 2) {
+            logger.warn({ streamId: stream.streamId }, 'Unexpected streamId format')
+            continue
+          }
+
+          const [ticker, bc] = parts
+
+          if (stream.type === 'ERROR') {
+            logger.error(
+              { streamId: stream.streamId, requestedId: stream.requestedId },
+              'SIX stream error',
+            )
+            results.push(makeRipcordResult(ticker, bc, 'SIX stream error (check entitlements)'))
+            continue
+          }
+
+          if (stream.type !== 'START' && stream.type !== 'UPDATE') continue
+
+          const lastPrice = stream.last?.value
+
+          if (lastPrice == null && stream.bestBid?.value == null && stream.bestAsk?.value == null) {
+            logger.debug({ streamId: stream.streamId }, 'No price data in message')
+            continue
+          }
+
+          const latestTimestamp =
+            stream.last?.unixTimestamp ??
+            stream.bestBid?.unixTimestamp ??
+            stream.bestAsk?.unixTimestamp
+          if (latestTimestamp != null) {
+            const ageS = Date.now() / 1000 - latestTimestamp
+            if (ageS > STALE_DATA_THRESHOLD_SECONDS) {
+              logger.warn(
+                { streamId: stream.streamId, ageS: Math.round(ageS) },
+                'Stale data detected',
+              )
+              results.push(makeRipcordResult(ticker, bc, `Stale data (${Math.round(ageS)}s old)`))
+              continue
+            }
+          }
+
+          ensureMarketStatusFetched(bc, context.adapterSettings.REST_API_ENDPOINT)
+          const marketStatus = marketStatusByBc.get(bc) ?? MARKET_STATUS_UNKNOWN
+
+          const mid =
+            stream.mid?.value ??
+            (stream.bestBid?.value != null && stream.bestAsk?.value != null
+              ? (stream.bestBid.value + stream.bestAsk.value) / 2
+              : undefined)
+
+          const providerIndicatedTimeUnixMs = toMilliseconds(latestTimestamp)
+
+          results.push({
+            params: { ticker, bc },
+            response: {
+              result: lastPrice ?? mid ?? null,
+              data: {
+                mid,
+                bid: stream.bestBid?.value,
+                bidSize: stream.bestBid?.size,
+                ask: stream.bestAsk?.value,
+                askSize: stream.bestAsk?.size,
+                lastTradedPrice: lastPrice,
+                volume: stream.volume?.value,
+                marketStatus,
+                ripcord: false,
+                ripcordAsInt: 0,
+              },
+              timestamps: {
+                providerIndicatedTimeUnixMs,
+              },
+            },
+          })
+        }
+
+        return results
+      },
+
+      error: (errorEvent) => {
+        logger.error({ errorEvent }, 'SIX WebSocket error')
+      },
+
+      close: (closeEvent) => {
+        const code = (closeEvent as any)?.code
+        const reason = (closeEvent as any)?.reason
+        const wasClean = (closeEvent as any)?.wasClean
+        logger.info({ code, reason, wasClean }, 'SIX WebSocket closed')
+      },
+    },
+
+    builders: {
+      subscribeMessage: (params, { adapterSettings: { CONFLATION_PERIOD } }) => ({
+        query: buildSubscriptionQuery(params.ticker, params.bc, CONFLATION_PERIOD),
+      }),
+
+      unsubscribeMessage: (params) => ({
+        query: buildCloseStreamQuery(params.ticker, params.bc),
+      }),
+    },
+  })
+
+  return transport
+}
diff --git a/packages/sources/six/src/transport/utils.ts b/packages/sources/six/src/transport/utils.ts
new file mode 100644
index 00000000000..06d54740d1a
--- /dev/null
+++ b/packages/sources/six/src/transport/utils.ts
@@ -0,0 +1,76 @@
+/**
+ * Build a GraphQL subscription query for SIX streaming market data.
+ */
+export const buildSubscriptionQuery = (
+  ticker: string,
+  bc: string,
+  conflationPeriod: string,
+): string => {
+  const streamId = `${ticker}_${bc}`
+  return `subscription {
+    startStream(
+      scheme: TICKER_BC,
+      ids: ["${streamId}"],
+      streamId: "${streamId}",
+      conflationType: INTERVAL,
+      conflationPeriod: "${conflationPeriod}"
+    ) {
+      type
+      requestedId
+      streamId
+      requestedScheme
+      last { value size unixTimestamp }
+      bestBid { value size unixTimestamp }
+      bestAsk { value size unixTimestamp }
+      mid { value unixTimestamp }
+      volume { value unixTimestamp }
+    }
+  }`
+}
+
+/**
+ * Build a GraphQL mutation to close a stream.
+ */
+export const buildCloseStreamQuery = (ticker: string, bc: string): string => {
+  const streamId = `${ticker}_${bc}`
+  return `mutation { closeStream(streamId: "${streamId}") { type streamId } }`
+}
+
+/**
+ * v11 marketStatus uint32 enum values.
+ *
+ *   0 = unknown
+ *   1 = pre-market
+ *   2 = open
+ *   3 = post-market
+ *   4 = closed
+ */
+export const MARKET_STATUS_UNKNOWN = 0
+export const MARKET_STATUS_PRE_MARKET = 1
+export const MARKET_STATUS_OPEN = 2
+export const MARKET_STATUS_POST_MARKET = 3
+export const MARKET_STATUS_CLOSED = 4
+
+/**
+ * Map SIX Market Base `marketStatus` enum (ACTIVE/INACTIVE/REFERENCE_ONLY/OTHER)
+ * to the Chainlink Data Streams v11 RWA Advanced `marketStatus` uint32.
+ */
+const MARKET_BASE_STATUS_MAP: Record<string, number> = {
+  ACTIVE: MARKET_STATUS_OPEN,
+  INACTIVE: MARKET_STATUS_CLOSED,
+  REFERENCE_ONLY: MARKET_STATUS_UNKNOWN,
+  OTHER: MARKET_STATUS_UNKNOWN,
+}
+
+export const mapMarketBaseStatusToV11 = (status: string | undefined): number => {
+  if (!status) return MARKET_STATUS_UNKNOWN
+  return MARKET_BASE_STATUS_MAP[status.toUpperCase()] ?? MARKET_STATUS_UNKNOWN
+}
+
+/**
+ * Convert SIX unix timestamp (seconds with microsecond precision) to milliseconds.
+ */
+export const toMilliseconds = (unixTimestamp: number | undefined): number | undefined => {
+  if (unixTimestamp == null) return undefined
+  return Math.round(unixTimestamp * 1e3)
+}
diff --git a/packages/sources/six/test-payload.json b/packages/sources/six/test-payload.json
new file mode 100644
index 00000000000..b914d7f1d54
--- /dev/null
+++ b/packages/sources/six/test-payload.json
@@ -0,0 +1,6 @@
+{
+  "requests": [{
+    "ticker": "ANA",
+    "bc": "1058"
+  }]
+}
diff --git a/packages/sources/six/test/integration/adapter.test.ts b/packages/sources/six/test/integration/adapter.test.ts
new file mode 100644
index 00000000000..0de6e9a72b6
--- /dev/null
+++ b/packages/sources/six/test/integration/adapter.test.ts
@@ -0,0 +1,139 @@
+import { WebSocketClassProvider } from '@chainlink/external-adapter-framework/transports'
+import {
+  mockWebSocketProvider,
+  MockWebsocketServer,
+  setEnvVariables,
+  TestAdapter,
+} from '@chainlink/external-adapter-framework/util/testing-utils'
+import FakeTimers from '@sinonjs/fake-timers'
+import nock from 'nock'
+import { mockWebSocketServer } from './fixtures'
+
+describe('SIX Adapter', () => {
+  let oldEnv: NodeJS.ProcessEnv
+  let mockWsServer: MockWebsocketServer
+  let testAdapter: TestAdapter
+  let marketBaseScope: nock.Scope
+  const wsEndpoint = 'ws://localhost:9090'
+  const restEndpoint = 'https://api.six-group.test'
+
+  beforeAll(async () => {
+    oldEnv = JSON.parse(JSON.stringify(process.env))
+
+    process.env['WS_API_ENDPOINT'] = wsEndpoint
+    process.env['REST_API_ENDPOINT'] = restEndpoint
+    process.env['TLS_PUBLIC_KEY'] = Buffer.from('mock-cert').toString('base64')
+    process.env['TLS_PRIVATE_KEY'] = Buffer.from('mock-key').toString('base64')
+    process.env['WS_SUBSCRIPTION_TTL'] = '5000'
+    process.env['CACHE_MAX_AGE'] = '5000'
+    process.env['CACHE_POLLING_MAX_RETRIES'] = '0'
+    process.env['METRICS_ENABLED'] = 'false'
+    process.env['WS_SUBSCRIPTION_UNRESPONSIVE_TTL'] = '30000'
+
+    // Mock Market Base REST endpoint for any BC - always returns ACTIVE
+    marketBaseScope = nock(restEndpoint)
+      .get('/web/v2/markets/referenceData/marketBase')
+      .query(true)
+      .reply(200, {
+        data: {
+          markets: [
+            {
+              lookupStatus: 'FOUND',
+              referenceData: { marketBase: { marketStatus: 'ACTIVE' } },
+            },
+          ],
+        },
+      })
+      .persist()
+
+    mockWebSocketProvider(WebSocketClassProvider)
+    mockWsServer = mockWebSocketServer(wsEndpoint)
+
+    const adapter = (await import('../../src')).adapter
+    testAdapter = await TestAdapter.startWithMockedCache(adapter, {
+      clock: FakeTimers.install(),
+      testAdapter: {} as TestAdapter<never>,
+    })
+
+    // Prime subscriptions so the background loop establishes WS and populates cache
+    await testAdapter.request({ ticker: 'ANA', bc: '1058' })
+    await testAdapter.request({ ticker: 'ABBN', bc: '4' })
+    await testAdapter.request({ ticker: 'STALE', bc: '999' })
+    await testAdapter.waitForCache(3)
+  })
+
+  afterAll(async () => {
+    // Verify the Market Base REST endpoint was actually called during tests
+    expect(marketBaseScope.isDone()).toBe(true)
+    nock.cleanAll()
+    setEnvVariables(oldEnv)
+    mockWsServer?.close()
+    testAdapter.clock?.uninstall()
+    await testAdapter.api.close()
+  })
+
+  describe('price endpoint', () => {
+    it('should return success for entitled BME instrument', async () => {
+      const response = await testAdapter.request({
+        ticker: 'ANA',
+        bc: '1058',
+      })
+
+      expect(response.statusCode).toBe(200)
+
+      const body = response.json()
+      expect(body.statusCode).toBe(200)
+      expect(body).toHaveProperty('data')
+      expect(body).toHaveProperty('result')
+
+      const d = body.data
+      expect(typeof d.bid).toBe('number')
+      expect(typeof d.ask).toBe('number')
+      expect(typeof d.lastTradedPrice).toBe('number')
+      expect(typeof d.volume).toBe('number')
+      expect(d.ripcord).toBe(false)
+      expect(d.ripcordAsInt).toBe(0)
+
+      expect(d.bid).toBe(230.8)
+      expect(d.ask).toBe(231.6)
+      expect(d.lastTradedPrice).toBe(231.6)
+      expect(d.mid).toBe(231.2)
+      expect(d.volume).toBe(53750.0)
+    })
+
+    it('should return ripcord error for non-entitled instrument', async () => {
+      const response = await testAdapter.request({
+        ticker: 'ABBN',
+        bc: '4',
+      })
+
+      const body = response.json()
+      expect(body.statusCode).toBe(502)
+      expect(body.errorMessage).toContain('Ripcord activated for ABBN_4')
+      expect(body.errorMessage).toContain('SIX stream error')
+    })
+
+    it('should return ripcord for stale data', async () => {
+      const response = await testAdapter.request({
+        ticker: 'STALE',
+        bc: '999',
+      })
+
+      const body = response.json()
+      expect(body.statusCode).toBe(502)
+      expect(body.errorMessage).toContain('Ripcord activated for STALE_999')
+      expect(body.errorMessage).toContain('Stale data')
+    })
+
+    it('should work with alias parameters', async () => {
+      const response = await testAdapter.request({
+        symbol: 'ANA',
+        market: '1058',
+      })
+
+      expect(response.statusCode).toBe(200)
+      const body = response.json()
+      expect(body.data.lastTradedPrice).toBe(231.6)
+    })
+  })
+})
diff --git a/packages/sources/six/test/integration/fixtures.ts b/packages/sources/six/test/integration/fixtures.ts
new file mode 100644
index 00000000000..da9f3a90ba5
--- /dev/null
+++ b/packages/sources/six/test/integration/fixtures.ts
@@ -0,0 +1,179 @@
+import { MockWebsocketServer } from '@chainlink/external-adapter-framework/util/testing-utils'
+
+export const mockStartResponse = {
+  data: {
+    startStream: [
+      {
+        type: 'START',
+        requestedId: 'ANA_1058',
+        streamId: 'ANA_1058',
+        requestedScheme: 'TICKER_BC',
+        last: {
+          value: 231.6,
+          size: 40.0,
+          unixTimestamp: Date.now() / 1000, // Fresh timestamp
+        },
+        bestBid: {
+          value: 230.8,
+          size: 20.0,
+          unixTimestamp: Date.now() / 1000,
+        },
+        bestAsk: {
+          value: 231.6,
+          size: 165.0,
+          unixTimestamp: Date.now() / 1000,
+        },
+        mid: {
+          value: 231.2,
+          unixTimestamp: Date.now() / 1000,
+        },
+        volume: {
+          value: 53750.0,
+          unixTimestamp: Date.now() / 1000,
+        },
+      },
+    ],
+  },
+}
+
+export const mockUpdateResponse = {
+  data: {
+    startStream: [
+      {
+        type: 'UPDATE',
+        requestedId: 'ANA_1058',
+        streamId: 'ANA_1058',
+        requestedScheme: 'TICKER_BC',
+        bestBid: {
+          value: 231.0,
+          size: 25.0,
+          unixTimestamp: Date.now() / 1000,
+        },
+        bestAsk: {
+          value: 231.8,
+          size: 150.0,
+          unixTimestamp: Date.now() / 1000,
+        },
+      },
+    ],
+  },
+}
+
+export const mockErrorResponse = {
+  data: {
+    startStream: [
+      {
+        type: 'ERROR',
+        requestedId: 'ABBN_4',
+        streamId: 'ABBN_4',
+        requestedScheme: 'TICKER_BC',
+      },
+    ],
+  },
+}
+
+// Stale timestamps must be relative to the fake clock (epoch 0).
+// 600s in the past from epoch 0 = negative timestamp, so we use a small positive
+// timestamp that will be >300s old once the fake clock advances past ~302s.
+// Since fake clock starts at 0 and the test runs quickly, a timestamp of 0 minus
+// STALE_DATA_THRESHOLD_SECONDS (300) in the transport means any timestamp older than
+// (currentTime - 300s) is stale. At fake time ~1s, anything < -299s is stale.
+// We can't use negative timestamps, so we set timestamp to 0 and rely on the
+// fake clock not advancing much — but the transport compares Date.now()/1000 - timestamp.
+// With fake timers Date.now() returns ~1 (1 second), so age = 1 - 0 = 1s — NOT stale.
+// Solution: use a very old real-world timestamp that will always be stale.
+const VERY_OLD_TIMESTAMP = 1000000
+export const mockStaleDataResponse = {
+  data: {
+    startStream: [
+      {
+        type: 'START',
+        requestedId: 'STALE_999',
+        streamId: 'STALE_999',
+        requestedScheme: 'TICKER_BC',
+        last: {
+          value: 100.0,
+          size: 10.0,
+          unixTimestamp: VERY_OLD_TIMESTAMP,
+        },
+        bestBid: {
+          value: 99.5,
+          size: 50.0,
+          unixTimestamp: VERY_OLD_TIMESTAMP,
+        },
+        bestAsk: {
+          value: 100.5,
+          size: 50.0,
+          unixTimestamp: VERY_OLD_TIMESTAMP,
+        },
+      },
+    ],
+  },
+}
+
+export const mockApiErrorResponse = {
+  errors: [
+    {
+      message: 'User does not have access to the requested quality of service',
+      category: 'ENTITLEMENT_ERROR',
+      type: 'ACCESS_DENIED',
+      messageCode: 3001,
+    },
+  ],
+}
+
+const makeStaleResponse = () => {
+  // Use Date.now() at call time so it captures fake clock value,
+  // then subtract enough to exceed STALE_DATA_THRESHOLD_SECONDS (300s)
+  const staleTimestamp = Date.now() / 1000 - 600
+  return {
+    data: {
+      startStream: [
+        {
+          type: 'START',
+          requestedId: 'STALE_999',
+          streamId: 'STALE_999',
+          requestedScheme: 'TICKER_BC',
+          last: { value: 100.0, size: 10.0, unixTimestamp: staleTimestamp },
+          bestBid: { value: 99.5, size: 50.0, unixTimestamp: staleTimestamp },
+          bestAsk: { value: 100.5, size: 50.0, unixTimestamp: staleTimestamp },
+        },
+      ],
+    },
+  }
+}
+
+export const mockWebSocketServer = (URL: string): MockWebsocketServer => {
+  const mockWsServer = new MockWebsocketServer(URL, { mock: false })
+  mockWsServer.on('connection', (socket) => {
+    socket.on('message', (msg) => {
+      const parsed = JSON.parse(msg.toString())
+      const query = parsed.query || ''
+
+      if (query.includes('ABBN_4')) {
+        socket.send(JSON.stringify(mockErrorResponse))
+      } else if (query.includes('STALE_999')) {
+        socket.send(JSON.stringify(makeStaleResponse()))
+      } else if (query.includes('closeStream')) {
+        socket.send(
+          JSON.stringify({
+            data: { closeStream: [{ type: 'STOP', streamId: 'ANA_1058' }] },
+          }),
+        )
+      } else {
+        // Fresh timestamps based on current (fake) clock
+        const now = Date.now() / 1000
+        const fresh = JSON.parse(JSON.stringify(mockStartResponse))
+        for (const s of fresh.data.startStream) {
+          if (s.last) s.last.unixTimestamp = now
+          if (s.bestBid) s.bestBid.unixTimestamp = now
+          if (s.bestAsk) s.bestAsk.unixTimestamp = now
+          if (s.mid) s.mid.unixTimestamp = now
+          if (s.volume) s.volume.unixTimestamp = now
+        }
+        socket.send(JSON.stringify(fresh))
+      }
+    })
+  })
+  return mockWsServer
+}
diff --git a/packages/sources/six/test/unit/utils.test.ts b/packages/sources/six/test/unit/utils.test.ts
new file mode 100644
index 00000000000..c5df9619a3f
--- /dev/null
+++ b/packages/sources/six/test/unit/utils.test.ts
@@ -0,0 +1,73 @@
+import {
+  buildCloseStreamQuery,
+  buildSubscriptionQuery,
+  mapMarketBaseStatusToV11,
+  MARKET_STATUS_CLOSED,
+  MARKET_STATUS_OPEN,
+  MARKET_STATUS_UNKNOWN,
+} from '../../src/transport/utils'
+
+describe('buildSubscriptionQuery', () => {
+  it('builds a valid GraphQL subscription with conflation', () => {
+    const query = buildSubscriptionQuery('ABBN', '4', 'PT1S')
+    expect(query).toContain('startStream')
+    expect(query).toContain('TICKER_BC')
+    expect(query).toContain('"ABBN_4"')
+    expect(query).toContain('streamId: "ABBN_4"')
+    expect(query).toContain('conflationType: INTERVAL')
+    expect(query).toContain('conflationPeriod: "PT1S"')
+    expect(query).toContain('last { value size unixTimestamp }')
+    expect(query).toContain('bestBid { value size unixTimestamp }')
+    expect(query).toContain('bestAsk { value size unixTimestamp }')
+    expect(query).toContain('mid { value unixTimestamp }')
+    expect(query).toContain('volume { value unixTimestamp }')
+  })
+
+  it('uses the provided conflation period', () => {
+    const query = buildSubscriptionQuery('ANA', '1058', 'PT0.5S')
+    expect(query).toContain('"ANA_1058"')
+    expect(query).toContain('conflationPeriod: "PT0.5S"')
+  })
+})
+
+describe('buildCloseStreamQuery', () => {
+  it('builds a valid closeStream mutation', () => {
+    const query = buildCloseStreamQuery('ABBN', '4')
+    expect(query).toContain('closeStream')
+    expect(query).toContain('streamId: "ABBN_4"')
+    expect(query).toContain('type')
+    expect(query).toContain('streamId')
+  })
+})
+
+describe('mapMarketBaseStatusToV11', () => {
+  it('maps ACTIVE to open (2)', () => {
+    expect(mapMarketBaseStatusToV11('ACTIVE')).toBe(MARKET_STATUS_OPEN)
+  })
+
+  it('maps INACTIVE to closed (4)', () => {
+    expect(mapMarketBaseStatusToV11('INACTIVE')).toBe(MARKET_STATUS_CLOSED)
+  })
+
+  it('maps REFERENCE_ONLY to unknown (0)', () => {
+    expect(mapMarketBaseStatusToV11('REFERENCE_ONLY')).toBe(MARKET_STATUS_UNKNOWN)
+  })
+
+  it('maps OTHER to unknown (0)', () => {
+    expect(mapMarketBaseStatusToV11('OTHER')).toBe(MARKET_STATUS_UNKNOWN)
+  })
+
+  it('is case-insensitive', () => {
+    expect(mapMarketBaseStatusToV11('active')).toBe(MARKET_STATUS_OPEN)
+    expect(mapMarketBaseStatusToV11('Inactive')).toBe(MARKET_STATUS_CLOSED)
+  })
+
+  it('returns unknown (0) for undefined', () => {
+    expect(mapMarketBaseStatusToV11(undefined)).toBe(MARKET_STATUS_UNKNOWN)
+  })
+
+  it('returns unknown (0) for unrecognized statuses', () => {
+    expect(mapMarketBaseStatusToV11('SOMETHING_ELSE')).toBe(MARKET_STATUS_UNKNOWN)
+    expect(mapMarketBaseStatusToV11('')).toBe(MARKET_STATUS_UNKNOWN)
+  })
+})
diff --git a/packages/sources/six/tsconfig.json b/packages/sources/six/tsconfig.json
new file mode 100644
index 00000000000..f59363fd76c
--- /dev/null
+++ b/packages/sources/six/tsconfig.json
@@ -0,0 +1,9 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "compilerOptions": {
+    "outDir": "dist",
+    "rootDir": "src"
+  },
+  "include": ["src/**/*", "src/**/*.json"],
+  "exclude": ["dist", "**/*.spec.ts", "**/*.test.ts"]
+}
diff --git a/packages/sources/six/tsconfig.test.json b/packages/sources/six/tsconfig.test.json
new file mode 100644
index 00000000000..e3de28cb5c0
--- /dev/null
+++ b/packages/sources/six/tsconfig.test.json
@@ -0,0 +1,7 @@
+{
+  "extends": "../../tsconfig.base.json",
+  "include": ["src/**/*", "**/test", "src/**/*.json"],
+  "compilerOptions": {
+    "noEmit": true
+  }
+}
diff --git a/packages/tsconfig.json b/packages/tsconfig.json
index d4ffaadaa42..012d5cf382d 100644
--- a/packages/tsconfig.json
+++ b/packages/tsconfig.json
@@ -446,6 +446,9 @@
     {
       "path": "./sources/securitize"
     },
+    {
+      "path": "./sources/six"
+    },
     {
       "path": "./sources/snowflake"
     },
diff --git a/packages/tsconfig.test.json b/packages/tsconfig.test.json
index 07cd9c69557..f480439e041 100644
--- a/packages/tsconfig.test.json
+++ b/packages/tsconfig.test.json
@@ -446,6 +446,9 @@
     {
       "path": "./sources/securitize/tsconfig.test.json"
     },
+    {
+      "path": "./sources/six/tsconfig.test.json"
+    },
     {
       "path": "./sources/snowflake/tsconfig.test.json"
     },
diff --git a/yarn.lock b/yarn.lock
index d025ea6bee8..0286e8bf63a 100644
--- a/yarn.lock
+++ b/yarn.lock
@@ -4806,6 +4806,24 @@ __metadata:
   languageName: unknown
   linkType: soft
 
+"@chainlink/six-adapter@workspace:packages/sources/six":
+  version: 0.0.0-use.local
+  resolution: "@chainlink/six-adapter@workspace:packages/sources/six"
+  dependencies:
+    "@chainlink/external-adapter-framework": "npm:2.13.1"
+    "@sinonjs/fake-timers": "npm:9.1.2"
+    "@types/jest": "npm:^29.5.14"
+    "@types/node": "npm:22.14.1"
+    "@types/sinonjs__fake-timers": "npm:8.1.5"
+    "@types/ws": "npm:^8"
+    axios: "npm:1.13.4"
+    nock: "npm:13.5.6"
+    tslib: "npm:2.4.1"
+    typescript: "npm:5.8.3"
+    ws: "npm:^8.18.3"
+  languageName: unknown
+  linkType: soft
+
 "@chainlink/snowflake-adapter@workspace:packages/sources/snowflake":
   version: 0.0.0-use.local
   resolution: "@chainlink/snowflake-adapter@workspace:packages/sources/snowflake"