ETP stands for exchange-traded product. The "exchange" refers to national securities exchanges and other security trading venues.
ETPs are regulated by the U.S. Securities and Exchange Commission ("SEC"). There are a vast number of them and they range from stock index- to currency- to commodity-based instruments targeted to investors seeking exposure to the price attributes of the underlying products absent a mechanism for acquiring the products.
ETFs are a form of ETP. On June 30, 2016 Cboe's then independent Bats BZX Exchange applied to the SEC for permission to amend its rules in order to list an ETF on bitcoin prices generated on the Gemini exchange. Noting the very early stage of development of the bitcoin marketplace, the SEC disapproved the rule change on March 10, 2017 due to the lack of information sharing agreements between the ETF-listing exchange and the spot market exchanges for bitcoin.
On January 4, 2018 NYSE Arca applied to the SEC for rule changes that would allow it to list bitcoin-based ETFs. The SEC requested public comment on January 24 regarding the application and in March provided notice that it might disapprove it. Based on the public comment notice date of January 24 the SEC extended its statutory review time on July 23 until September 24.