Gossamer Bio is trading 5.3% down at $9.25 in pre-market, versus its October 27 close of $9.77; no overnight event explaining the decline is confirmed. - The decline follows a 6.78% gain in the prior session. - The up-to-$250 million structured private placement was announced on August 21, not as new October 28 news. - Broad pre-market indicators are mixed and do not clearly explain the stock-specific decline.