The Insights Association and Marketing Research and Intelligence Association (MRIA) have joined forces to criticise Apple for an update in its Safari browser, launched last month, which limits how advertisers and websites can track users. 

In a letter addressed to Craig Federighi, senior vice-president of software engineering at Apple, the Insights Association and MRIA claimed that the ‘intelligent tracking prevention’ system in Safari poses "a severe and almost insuperable problem for online marketing research and analytics, including consent-based online audience measurement and user experience research".

These “essential measures” are depended upon by brands and organisations to operate, the letter said.

It also warned that companies would be forced to "fly blind" without the insights provided by market research and analytics. 

"Without the insights provided by robust online marketing research and analytics, you are forcing companies to fly blind without the ability to measure and verify. Meanwhile, users of the Safari browser have lost much of their ability to opt out of tracking and control their own privacy."

The Safari update was met with condemnation from advertising industry groups when it launched in September, with six trade bodies including the Interactive Advertising Bureau and American Advertising Federation publishing an open letter in September blasting Apple for blocking cookies.