** Shares of ad-tech firm Trade Desk TTD.O plunge 27% to $89.81 premarket

** Q1 revenue forecast falls short of estimates on softer demand for its digital advertising services in the connected TV market

** The outlook is for the period following the holiday season where analysts expected retailers to double down on advertising, with a focus on political ad spending during the U.S. presidential elections

** Q4 revenue also misses estimates, the first top-line miss for the company in at least five years, per LSEG data

** At least five brokerages trim PT on stock after results

** "There were likely several factors leading to the first ever miss in company history, but mgmt primarily cited the sales reorganization and subsequently slower than expected adoption of Kokai" - Jefferies

** TTD shares up 65% over the past 12 months compared to 23% rise in the Nasdaq 100 .NDX

(Reporting by Medha Singh)

((medha.singh@thomsonreuters.com))