Nasdaq-listed ALT5 Sigma Corporation has seen its share price fall 80% following its August announcement to accumulate World Liberty Financial (WLFI) tokens. The fintech firm, which repositioned itself as a digital asset treasury in 2024, now faces executive departures, potential regulatory scrutiny, and investor backlash. The company had proposed raising $1.5 billion for WLFI token reserves, but the initiative faces mounting challenges from internal instability and governance concerns.

South Korean crypto exchange Upbit disclosed a security incident on November 27 involving approximately $36m in Solana-based assets transferred to an unknown wallet. The platform immediately suspended deposit and withdrawal services and committed to covering all losses from its own reserves without impacting customer balances. The breach occurred nearly six years after Upbit lost 342,000 ETH to North Korean actors in a November 2019 attack.

Three large traders established combined long positions worth $92.87 million on Bitcoin and Ethereum through Hyperliquid on November 26, data show. The positions utilized leverage ranging from 2x to 25x. Separately, Ethereum co-founder Vitalik Buterin transferred $2.9 million in ETH to privacy protocol Railgun.

South Korean technology conglomerate Naver announced the acquisition of Dunamu, operator of cryptocurrency exchange Upbit, in an all-stock transaction valued at $10.3 billion on November 26. Dunamu will become a wholly owned subsidiary of Naver Financial upon completion. Upbit commands over 80% of South Korea's cryptocurrency market share.

S&P Global has downgraded Tether's USDT stablecoin to a stability rating of '5,' the lowest on its assessment scale. The ratings agency cited elevated exposure to risky assets and inadequate reserve buffers as primary concerns. Tether's risky asset ratio has reached 24%, with Bitcoin exposure at 5.6% exceeding S&P's recommended buffer threshold of 3.9%.

The UK government is considering expanding Treasury bill issuance through its Debt Management Office to diversify short-term debt investors and strengthen sterling markets. The move responds to rising demand from new participants, including stablecoin issuers seeking liquid, low-risk assets. A consultation on expanding the ultra-short-dated debt market will begin in January.

S&P Global Ratings downgraded Tether's USDT stablecoin to 'weak' from 'constrained', citing exposure to high-risk assets and limited reserve transparency. The agency warned that Bitcoin holdings—now 5.4% of reserves—combined with other volatile assets could reduce collateral coverage if valuations decline. Tether has not conducted a complete audit since inception and lacks direct redemption channels for token holders, according to S&P.

S&P Global Ratings assigned Tether's USDT stablecoin its weakest stability assessment of 5, citing increased allocation to riskier reserve assets. Bitcoin holdings now represent approximately 5.6% of USDT's circulating supply, exceeding the 3.9% reserve buffer reported in Tether's third-quarter attestation. The agency warned that a significant bitcoin price decline could leave USDT undercollateralized, particularly if combined with losses from other high-risk assets.