Shares of advertising technology companies fell after BMO Capital said Apple’s (AAPL) changes to access ID for advertising presents a headwind from them. HEADWINDS FOR AD TECH: BMO Capital analyst Daniel Salmon downgraded Criteo (CRTO) to Market Perform from Outperform with a price target of $13, down from $16. Apple is making changes to access ID for advertising that present a headwind for advertising technology companies, Salmon told investors in a research note. While not the worst case scenario of immediate and complete elimination, Apple’s moves present risk to Criteo’s iOS app business in the near term as IDFA was a key signal used for targeting, attribution and other uses, noted the analyst. As a result, Salmon said he cannot recommend Criteo for new investment dollars “until we get greater clarity on the issue.” PRICE ACTION: Shares of Criteo fell 16% to $11.00 per share on Wednesday. PEERS TRADE LOWER: Criteo’s advertising technology peers also closed significantly lower, including Rubicon Project (RUBI), Cardlytics (CDLX), QuinStreet (QNST), Trade Desk (TTD), and TechTarget (TTGT).