Gemini data was set to join CME’s bitcoin settlement benchmark

Gemini and CF Benchmarks announced on August 8, 2019 that Gemini market data would be added to eight cryptocurrency indices on August 30. The group included the CME CF Bitcoin Reference Rate, the benchmark used to determine final settlement for CME’s cash-settled bitcoin futures, along with real-time bitcoin and ether indices.

The decision mattered because it placed transactions from another regulated U.S. spot venue inside pricing infrastructure used by a major derivatives marketplace. It was a change to the inputs behind benchmark prices, not the launch of a new coin, futures contract or exchange. Nor did Gemini data begin affecting the rates on August 8: both contemporaneous primary records set implementation for August 30.

What the announcement changed

CF Benchmarks, the benchmark administrator then formerly known as Crypto Facilities Indices, said Gemini would contribute data to eight indices. It specifically named the CME CF Bitcoin Reference Rate, or BRR; the CME CF Bitcoin Real Time Index, or BRTI; the CME CF Ether-Dollar Reference Rate; and the CME CF Ether-Dollar Real Time Index. Its announcement said Bitstamp, Coinbase, itBit and Kraken were already constituent exchanges across the relevant benchmark set.

Gemini said its inclusion followed review under CME Group eligibility criteria covering submitted-data quality, market surveillance, security and regulation. That statement describes the selection process represented by Gemini and supported by the administrator’s decision; the surviving announcement does not publish a scorecard, audit report or exchange-by-exchange comparison.

The scheduled start was August 30, 2019 at 4:30 p.m. British Summer Time. Until then, Gemini remained an announced future constituent rather than an active input under this change.

Why the benchmark connection mattered

CME’s bitcoin futures were cash settled. Instead of delivering bitcoin when a contract expired, the final settlement depended on the BRR, a once-daily U.S.-dollar reference price for one bitcoin. CME’s 2019 methodology description said the rate aggregated eligible BTC-USD transactions from constituent exchanges during the one-hour window from 3:00 p.m. to 4:00 p.m. London time.

That hour was divided into 12 five-minute partitions. A volume-weighted median was calculated for each partition, and the 12 results were equally weighted to produce the daily rate. The structure was intended to reduce dependence on a single trade or venue while remaining reproducible. The BRTI served a different function: it provided a continuously updated view rather than the daily settlement fixing.

Adding another constituent could broaden the pool of observed spot-market activity and reduce concentration in the benchmark’s inputs. That is an interpretation of the benchmark design, not proof that the August 30 rate would become more accurate by a measurable amount. Neither the August 8 announcement nor the available methodology supplied a forecast for Gemini’s future weight, transaction contribution or effect on any settlement value.

Institutional context and limits

CME had launched bitcoin futures for the December 18, 2017 trade date after self-certification with the Commodity Futures Trading Commission. At that launch, both CME and the CFTC emphasized that bitcoin’s underlying cash markets were comparatively young; the CFTC also noted limits on its statutory authority over those spot venues. Against that backdrop, constituent selection and benchmark methodology were central pieces of the bridge between cryptocurrency trading platforms and regulated derivatives.

The August 8 development did not establish that bitcoin or ether prices moved because of Gemini’s selection. No event-day price, return, volume or open-interest claim is made here, because the primary records document a benchmark-governance change rather than a measurable market reaction.

Later confirmation

A later CME operational notice recorded that Gemini data was included in the bitcoin and ether reference rates and real-time indices on August 30, 2019 at 10:30 a.m. Central Time. That later record confirms implementation; it is not used to imply that the change was already live on August 8.