The IRS requests cover around 10,000 Coinbase accounts with court documents noting that only 800 to 900 taxpayers reported gains related to bitcoin in each of the relevant years (2013-2015) suggesting that many Coinbase users may not be reporting their bitcoin gains!
today the court narrowed the scope of documents that the IRS can request from Coinbase to taxpayer ID number, name, date of birth, address, transaction logs and account statements, deeming the rest of the documents “not necessary.” Again, these personal data requests will only apply to accounts that have bought, sold, sent or received more than $20,000 in any of those types of transactions between 2013 and 2015. As the court documents specify, the narrowed IRS request “applies to far fewer, but still more than 10,000, Coinbase account holders.”
https://techcrunch.com/2017/11/29/coinbase-internal-revenue-service-taxation/