Etherdelta

Basics

• Decentralized Exchange
• EtherDelta users conducted more than 3.6 million trades over an 18-month period for ERC-20 tokens (10-2018)

History and SEC

• From Token Tuesdays (5-11-2019):

"Many token startups could not meet the aspirations set by their investors and never saw listings on top tier exchanges. The last resort for many investors was to create their own liquidity by using decentralized exchanges like EtherDelta, where listings were permissionless. In essence, all you needed was someone on the other end to buy or sell the underlying token.

Despite absolutely horrendous user experience, EtherDelta still grew to prominence throughout 2017 due to this notion of permissionless liquidity. Any project or investor could easily add their token details (contract address, ticker symbol, number of decimals, etc.) and boom, a trading pair to buy and sell the asset was created.
Unfortunately for EtherDelta,  the exchange faced an SEC lawsuit against the original founders in November of 2018. EtherDelta still lives on, (now known as ForkDelta) however, it does not get nearly as much volume as it did in its prime back in 2017 largely due to the terrible user experience." 

• The U.S. Securities and Exchange Commission (SEC) has charged Zachary Coburn, the founder of crypto token trading platform EtherDelta, with operating an unregistered securities exchange. Coburn has already settled the charges, according to the release. Though he did not admit to or deny the charges, he paid $300,000 in disgorgement, $13,000 in pre-judgement interest and a $75,000 penalty.  
• A legal analyses can be read here (6-12-2018).