The GSM Association has announced that it has stopped its development work on a standard for embedded SIMs or eSIMs. It also says that it is cooperating with an investigation by the the Department of Justice on an investigation.

The New York Times had reported on Friday that the department launched a probe in December on claims that AT&T, Verizon and the GSMA have colluded against the implementation of one of eSIM’s proposed tenets: that it would allow consumers to opt into carrier locking instead of having it on by default. Instead, the United States’s two largest carriers had lobbied to prevent users from switching the network alliance on their device at their will without the need to physically switch SIM cards. AT&T and Verizon have each said that the network was involved in the Justice Department’s action and are cooperating.

Other wireless carriers and many cellular device manufacturers have supported eSIM.

Verizon had agreed to sell and accept unlocked phones as part of its acquisition of 700MHz Block C spectrum in 2008, but has recently announced that it would begin selling its phones SIM-locked by default out of concern for “theft” and “fraud.”