The probability that Strategy will sell Bitcoin before May 31 has collapsed to 23% on Polymarket — down 17 percentage points in a single 24-hour period — after on-chain data showed the company withdrawing 411 BTC from Coinbase, the exact amount it had deposited the day before, in a move the market widely interpreted as an intentional signal against an imminent sale.The Polymarket dataPrediction market odds shifted sharply across all three Strategy sale timeframes tracked on Polymarket. The probability of a Bitcoin sale before May 31 dropped from approximately 40% to 23% — a 17% decline in 24 hours. The probability of a sale before June 30 fell 6% to 67%. The probability of a sale before December 31 declined 3% to 88%.The simultaneous drop across all three timeframes suggests the market is not simply pushing the sale timeline forward — it is genuinely reducing its conviction that a near-term sale will occur at all.The 411 BTC withdrawal: a deliberate signalThe catalyst for the odds collapse was an on-chain movement that carried its own message. Strategy withdrew 411 BTC from Coinbase on Thursday — precisely the same amount the company had deposited the previous day. A deposit followed immediately by a full withdrawal of the identical amount is not a routine treasury operation. It is the kind of on-chain behavior that sends a clear signal to a market watching Strategy's every blockchain move: the coins that came in went straight back out, with no sale occurring in between.The timing is significant. Strategy CEO Michael Saylor had raised the possibility of Bitcoin sales during the company's recent earnings call — framing potential disposals as a mechanism to protect Bitcoin's long-term value rather than a retreat from the accumulation thesis. That comment generated significant market anxiety and contributed to Polymarket assigning substantial odds of a near-term sale. Thursday's 411 BTC withdrawal-after-deposit appears to be a direct response to that anxiety — a way of demonstrating through on-chain action rather than words that no sale took place.