Wisconsin’s investment board saw fit to significantly add to its bitcoin (BTC) bet in the last three months of the year.

The State of Wisconsin Investment Board (SWIB) disclosed ownership of just over 6 million shares of BlackRock’s iShares Bitcoin Trust (IBIT) as of the Dec. 31, per a 13F filing on Friday, up from roughly 2.9 million shares three months prior.

The position was valued at $321 million as of year-end and would be worth about $588 million at bitcoin’s current price near $98,000.

The fund in 2024 became the first of its kind to report a bitcoin ETF purchase, initially buying 94,562 shares of IBIT and some shares of Grayscale’s Bitcoin Trust (GBTC), which it later sold.

The State of Michigan Retirement System later also reported owning shares of bitcoin ETFs, the ARK 21Shares Bitcoin ETF (ARKB) and two of Grayscale’s bitcoin products.

SWIB, established in 1951, oversees more than $156 billion in assets including funds from the Wisconsin Retirement System (WRS) and the State Investment Fund (SIF). The board manages investments on behalf of state employees and other trust funds.

Today marks the deadline for institutional investors managing at least $100 million in assets to report quarterly holdings to the Securities and Exchange Commission (SEC). The market is closely monitoring these filings to gauge whether large traditional finance firms have been adding bitcoin ETFs to their portfolios since their launch last year.

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