Eight of the 10 leading location analytics companies have agreed to a new code of conduct in an effort led by U.S. Sen. Charles Schumer, according to the Associated Press.

Schumer began sounding the alarm this summer, saying consumers should know when retailers are using their smartphones to track their movements through a store.

On Tuesday, Schumer told AP that the eight companies have agreed to a new code of conduct that includes signs posted in stores to alert shoppers that tracking is being done and instructions on how to opt out.

"This is a major step forward in the quest for consumer privacy," the New York Democrat said.

The technology companies are Euclid, iInside, Mexia Interactive, Nomi, SOLOMO, Radius Networks, Brickstream and Turnstyle Solutions, according to AP.

"Today, location analytics companies have introduced a comprehensive code to ensure they have data protection standards in place to de-identify data, to provide consumers with effective choices to not be tracked and to explain to consumers the purposes for which data is being used," Jules Polonetsky, the forum's executive director, told AP.

Under the code of conduct, the companies must get consumers' OK if they will be contacted later based on their tracking information, and the data won't be used adversely for determining eligibility for employment, credit, health care treatment or insurance.

The companies also agree to contractually require third-party data users also follow the code, AP said.

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