Senator Elizabeth Warren (D-MA) sent Apple CEO Tim Cook a letter asking for information regarding Cook and Apple’s conversations with President Donald Trump’s administration about tariffs and any special exemptions from the tariffs, Bloomberg reports.

Warren’s letter, obtained by Bloomberg, points out that Apple “appeared to have invested heavily in influencing the Trump Administration” through things like Cook’s $1 million donation to Trump’s inauguration and Cook’s presence at the inauguration. It discusses The Washington Post’s recent report about Cook’s discussions with White House officials, including a reported conversation with Commerce Secretary Howard Lutnick about how tariffs could impact the price of iPhones.

It also notes Trump’s tariff exemptions for smartphones and other electronics and quotes WaPo saying that “Apple appears to be the only company that benefits from virtually all of [them].”

Warren’s letter concludes with a list of questions for Apple, which includes inquiries on things like the nature of Cook’s discussions with the Trump administration, when Apple learned about the exemptions, and asking about the “the value of the additional profits that Apple will obtain as a result of President Trump’s tariff exemption.”

The letter does not include a deadline for Cook to respond. Apple didn’t immediately reply to a request for comment from The Verge.