OpenRouter and a16z report that open-weight models reached approximately one-third of token usage on OpenRouter by late 2025; an NBER working paper using OpenRouter and Microsoft Azure usage data reports a lower open-source share of OpenRouter tokens, about 25% by December 2025 after a peak near 45% in August.

SocioLens project,

Claim LD11-HQ-C14 (v1.1)

Research opportunities this claim motivates

What this claim leaves open for research. Each is a hypothesis about a gap, not a finding.

How large is open-weight model use beyond a single routing platform?The one-third open-weight token share is measured on OpenRouter only, and the claim does not license a global, enterprise or infrastructure-independence reading; this study tests how far it travels.
How much of the fall in AI prices is competition rather than cheaper technology?Open-weight models carry a substantial share of OpenRouter tokens, so the platform offers many identical-weights products sold by competing hosts, which is the natural setting for separating cost from margin; the claim itself says nothing about prices.

Provenance and status

Claim type: Estimate
Publication status: Eligible for publication, with a qualifier
Verification state: Checked against the primary source. Who checked this claim is not recorded for it; claim checks so far were AI-led, and no person has checked claims against their sources.
Does not license: Global model share, enterprise production share or infrastructure independence
Limitations: Single platform; developer/cost-sensitive selection; both sources are positioned (OpenRouter/a16z is the platform and an investor; Demirer et al. disclose Microsoft employment, equity and consulting and Amazon employment among the authors); the two analyses of the same platform disagree for late 2025 and the reason is not established; Demirer et al.'s introduction states the open-source share stays below 30%, while its Section 6.1 reports a 45% August peak
Source (as cited): OpenRouter/a16z, State of AI: 100 Trillion Token Study; Demirer, Fradkin, Tadelis & Peng, “The Emerging Market for Intelligence: Pricing, Supply, and Demand for LLMs,” NBER Working Paper 34608, December 2025
Source type: Preprint, Working paper (recorded as “Platform telemetry / preprint; Academic working paper”)
Institutional position: Platform + investor; Academic + industry (authors affiliated with Microsoft and Amazon)
Maturity of the evidence: Emerging evidence
Recorded date: 13 October 2026
Currentness / correction: This is the current version. No correction or concern is recorded on its sources.

Sources this version cites

Version

This is the current version, v1.1. Earlier versions stay available, and their records never change.

Versions: v1.0, v1.1 · current

What changed in this version

This version supersedes version v1.0 (LD11-HQ-C14--v1.0), which stays available with its record unchanged.

Changed fields: 2 PUBLIC-FACING CLAIM; 6 SOURCE; 7 SOURCE TYPE; 8 INSTITUTIONAL POSITION; 9 SCOPE; 11 SAMPLE / DATASET; 14 MAIN RESULT; 18 LIMITATIONS; 19 CONTRADICTORY / SUPPORTING SOURCES; 25 RECORDED DATE
What changed: The claim now reports, beside the OpenRouter/a16z figure, the lower open-source token share that Demirer, Fradkin, Tadelis & Peng (NBER Working Paper 34608, December 2025) report from OpenRouter data, and cites that paper as a second source. The OpenRouter/a16z figure is unchanged.
Why: A literature check on 13 October 2026 found a second analysis of the same platform, by academic authors with Microsoft and Amazon affiliations, that reports about 25% open-source share by December 2025, not about one-third. Version 1.0 cited only the platform's own report, so a reader could take one-third as settled. The figures were read from the NBER paper by AI agents, not by a person, to the same standard as the rest of this ledger (primary-text reading by AI, no named human expert).

Raw record: every recorded field, with its coded values

All 25 canonical Claim fields, verbatim, with the coded values derived from them. The plain-language labels above are read from these.

Claim type (coded): ESTIMATE (as printed: “ESTIMATE”)
Publication status (coded): ELIGIBLE (QUALIFIED) (as printed: “ELIGIBLE WITH QUALIFIER”)
Verification state (coded): CONTENT_VERIFIED_PRIMARY
Source type (coded): PREPRINT, WORKING_PAPER
Maturity (coded): EMERGING

#	Canonical field	Canonical value (verbatim)	Normalized (Claim Value Vocabulary v1.0.2)
1	CLAIM ID	LD11-HQ-C14	—
2	PUBLIC-FACING CLAIM	OpenRouter and a16z report that open-weight models reached approximately one-third of token usage on OpenRouter by late 2025; an NBER working paper using OpenRouter and Microsoft Azure usage data reports a lower open-source share of OpenRouter tokens, about 25% by December 2025 after a peak near 45% in August.	—
3	CLAIM TYPE	ESTIMATE	base_types: ESTIMATE
4	RESEARCH STRAND	C — Foundation-model market structure	—
5	MATURITY	EMERGING	states: EMERGING
6	SOURCE	OpenRouter/a16z, State of AI: 100 Trillion Token Study; Demirer, Fradkin, Tadelis & Peng, “The Emerging Market for Intelligence: Pricing, Supply, and Demand for LLMs,” NBER Working Paper 34608, December 2025	source_ids: SRC-LD11-OPENROUTER-A16Z-100T-TOKEN-STUDY, SRC-SL-DEMIRER-FRADKIN-TADELIS-PENG-NBER-34608
7	SOURCE TYPE	Platform telemetry / preprint; Academic working paper	classes: PREPRINT, WORKING_PAPER
8	INSTITUTIONAL POSITION	Platform + investor; Academic + industry (authors affiliated with Microsoft and Amazon)	—
9	SCOPE	OpenRouter routed tokens; global platform traffic; 2024–2025 (OpenRouter/a16z); January–December 2025 (Demirer et al.)	—
10	DESIGN	Observational telemetry	—
11	SAMPLE / DATASET	100+ trillion tokens (OpenRouter/a16z); OpenRouter and Microsoft Azure API usage data (Demirer et al.)	—
12	MODEL / TOOL / VERSION	Multiple open/proprietary models	—
13	COMPARATOR	Proprietary models	—
14	MAIN RESULT	Open weights reached ~one-third of weekly token volume by late 2025 (OpenRouter/a16z); open-source token share rose from about 25% in January 2025 to 45% by August and fell to 25% by December 2025 (Demirer et al.)	—
15	INFERENTIAL TARGET	Model-vendor counterpower on a large developer-oriented platform	—
16	DOES NOT LICENSE	Global model share, enterprise production share or infrastructure independence	—
17	VERIFICATION STATE	CONTENT VERIFIED	state: CONTENT_VERIFIED_PRIMARY · verified_by: UNKNOWN
18	LIMITATIONS	Single platform; developer/cost-sensitive selection; both sources are positioned (OpenRouter/a16z is the platform and an investor; Demirer et al. disclose Microsoft employment, equity and consulting and Amazon employment among the authors); the two analyses of the same platform disagree for late 2025 and the reason is not established; Demirer et al.'s introduction states the open-source share stays below 30%, while its Section 6.1 reports a 45% August peak	—
19	CONTRADICTORY / SUPPORTING SOURCES	Demirer et al. (NBER WP 34608) report a lower late-2025 open-source share from OpenRouter data; Menlo enterprise open-source measure is a different population	—
20	GEOGRAPHY / LANGUAGE	Global platform / English-dominant	—
21	DISTRIBUTIONAL LEDGER	Lower-cost/open-weight choices expand developer options	—
22	R01 / FIELD-MAP LINKS	D1, L-B, R-2, LD-11	—
23	WHAT WOULD CHANGE THIS CLAIM?	Independent multi-platform telemetry	—
24	PUBLICATION STATUS	ELIGIBLE WITH QUALIFIER	state: ELIGIBLE · qualifiers: QUALIFIED
25	RECORDED DATE	2026-10-13	—

Field 22 references resolved against Field Map v0.2: D1 (DOMAIN); L-B (LENS); R-2 (LENS); LD-11 (LIVING_DEBATE)

The sources as recorded, with their record IDs and coded source types:

Pinned Sources (field 6, version-specific)

“OpenRouter/a16z, State of AI: 100 Trillion Token Study” → OpenRouter/a16z, State of AI: 100 Trillion Token Study (SRC-LD11-OPENROUTER-A16Z-100T-TOKEN-STUDY--v1.0) — OpenRouter/a16z, State of AI: 100 Trillion Token Study; class PREPRINT (explicit public provenance pin)
“Demirer, Fradkin, Tadelis & Peng, “The Emerging Market for Intelligence: Pricing, Supply, and Demand for LLMs,” NBER Working Paper 34608, December 2025” → Demirer et al. (2025), “The Emerging Market for…” (SRC-SL-DEMIRER-FRADKIN-TADELIS-PENG-NBER-34608--v1.0) — Demirer, Fradkin, Tadelis & Peng, “The Emerging Market for Intelligence: Pricing, Supply, and Demand for LLMs,” NBER Working Paper 34608, December 2025; class WORKING_PAPER (explicit public provenance pin)

Cite this page

SocioLens project. (2026, October 13). OpenRouter and a16z report that open-weight models reached approximately one-third of token usage on OpenRouter by late 2025; an NBER working paper using OpenRouter and Microsoft Azure usage data reports a lower open-source share of OpenRouter tokens, about 25% by December 2025 after a peak near 45% in August [Claim LD11-HQ-C14, version v1.1]. SocioLens. https://sociolens-web.pages.dev/claims/ld11-hq-c14/v1.1/

@misc{sociolens_ld11_hq_c14_v1_1,
  author = {{SocioLens project}},
  title = {OpenRouter and a16z report that open-weight models reached approximately one-third of token usage on OpenRouter by late 2025; an NBER working paper using OpenRouter and Microsoft Azure usage data reports a lower open-source share of OpenRouter tokens, about 25\% by December 2025 after a peak near 45\% in August.},
  year = {2026},
  date = {2026-10-13},
  howpublished = {\url{https://sociolens-web.pages.dev/claims/ld11-hq-c14/v1.1/}},
  note = {Claim LD11-HQ-C14, version v1.1}
}

The link points to this version, whose record never changes. For a finding, cite the original study as well: SocioLens summarizes research and does not replace it.

Research-of-record provenance

Materialized by sociolens-materializer 0.6.0 at 2026-09-28T20:00:00.000Z; normalization contract SocioLens — Claim Value Vocabulary v1.0.2 — Pre-Spike Materialization Contract (v1.0.2). Content seal SHA-256 048bb2df4b92a77599b2a305229e742ec4cb7b1d3a36f1cca592b36ebfe2f00b.

Repository-authored inputs (not Drive exports)

SocioLens claim revision — LD11-HQ-C14 v1.1 (v1.1) — written in the SocioLens repository by Project Lead (Claude, AI) on 2026-10-13; no Drive identity exists. Authority: AGENTS.md "Authority" (the Project Lead decides research content within the research-integrity rules) and docs/PROJECT.md "Research revisions" (a published claim changes only through a new version that states what changed and why). Block “ENTRY 14 — LD11-HQ-C14” SHA-256 8bc1aafb6cded0d9477ce7c2a8fe73f6bc260c273f540c959379a81e6e0a812d; fixture fixtures/authored/claim-revisions/LD11-HQ-C14--v1.1.

Builder decisions (not Drive data)

VERSION = v1.1 — basis: Claim version taken from the repository-authored revision fixture version (SocioLens claim revision — LD11-HQ-C14 v1.1); a new version of LD11-HQ-C14 v1.0, which stays routable (AGENTS.md research integrity rule 3)
CURRENT_POINTER = true — basis: repository-authored revision "SocioLens claim revision — LD11-HQ-C14 v1.1" (Project Lead (Claude, AI), 2026-10-13); basis: AGENTS.md "Authority" (the Project Lead decides research content within the research-integrity rules) and docs/PROJECT.md "Research revisions" (a published claim changes only through a new version that states what changed and why)
FIELD_6_SOURCE_REFERENCE = SRC-LD11-OPENROUTER-A16Z-100T-TOKEN-STUDY--v1.0 — basis: field 6 of ENTRY 14 — LD11-HQ-C14 cites "OpenRouter/a16z, State of AI: 100 Trillion Token Study"; the first field-6 segment of this ClaimVersion's repository-authored ledger block; the same Source record LD11-HQ-C14 v1.0 cites.
FIELD_6_SOURCE_REFERENCE = SRC-SL-DEMIRER-FRADKIN-TADELIS-PENG-NBER-34608--v1.0 — basis: field 6 of ENTRY 14 — LD11-HQ-C14 cites "Demirer, Fradkin, Tadelis & Peng, “The Emerging Market for Intelligence: Pricing, Supply, and Demand for LLMs,” NBER Working Paper 34608, December 2025"; the second field-6 segment of this ClaimVersion's repository-authored ledger block; the NBER working paper added by this revision.
SOURCE_PROVENANCE_PIN = SRC-LD11-OPENROUTER-A16Z-100T-TOKEN-STUDY--v1.0 — basis: explicit version-pinned public provenance of this ClaimVersion (Amendment v1.2 §6): the pinned field-6 Source record "OpenRouter/a16z, State of AI: 100 Trillion Token Study".
SOURCE_PROVENANCE_PIN = SRC-SL-DEMIRER-FRADKIN-TADELIS-PENG-NBER-34608--v1.0 — basis: explicit version-pinned public provenance of this ClaimVersion (Amendment v1.2 §6): the pinned field-6 Source record for NBER Working Paper 34608.