Coinbase now simply blocks "post-only" buy orders priced above the current market instead of accepting and then canceling them, a small but telling change for Bitcoin traders.

• The "post-only" setting is meant for market makers who only want to add orders to the book, never take an existing one.
• Trying to place a post-only buy order far above the current price used to get accepted and then instantly canceled.
• Now the exchange won't let the order into the book at all, skipping the accept-then-cancel step.
• This is a minor technical change, not a market-moving event, but shows exchanges are tightening order-matching rules.

Outlook: No real impact on Bitcoin's price expected; this is a platform mechanics tweak, not a market signal.