Federal prosecutors unseal an indictment charging two Volkswagen engineers with insider trading tied to Volkswagen’s joint venture with Rivian. According to the allegations, the two engineers—Michael Stamp and Marcus Plank—use confidential, nonpublic information to purchase Rivian stock before the company’s multibillion-dollar joint venture with the electric vehicle maker is publicly announced.

The cases are filed in connection with activities conducted through Volkswagen’s U.S. operations. Prosecutors say the engineers had access to information related to the joint venture prior to its public disclosure and then traded Rivian shares during that period.

Both engineers are arrested in San Jose, California, and the indictment is unsealed on Friday. Each defendant faces one count of federal securities fraud, as described by the sources. The reports focus on the timing of the stock purchases relative to the public announcement of the joint venture and the claim that confidential information was used for the trades. The sources do not indicate whether the defendants have pleaded or whether the allegations involve any additional trades beyond the reported purchases.