Ambarella's stock experienced a significant pre-market plunge of 5.47% on Friday, moving against a backdrop of mostly positive analyst actions on the chipmaker.

The sharp decline appears to be driven primarily by a rating downgrade from Summit Insights Group, which cut its rating on Ambarella to Hold. This negative action seemingly overshadowed several positive analyst notes issued around the same time, including price target increases from Stifel, BofA Global Research, and Susquehanna.

Market participants reacted to the downgrade by selling shares in pre-market trading, indicating concerns that may have been triggered by the more cautious stance from Summit Insights Group despite other firms maintaining bullish outlooks on the company.