On Friday, short-seller Muddy Waters Research reiterated an offer made a day earlier to publicly debate Tesla Inc. Chief Executive Officer Elon Musk on the merits of short selling.

Muddy Waters made the initial offer late on Thursday after Musk criticized the practice of short-selling repeatedly on Twitter.

Muddy Waters Twitter account specifically responded to Musk’s assertion that short-sellers are value destroyers.

Exactly. Short-sellers are value destroyers. Should definitely be illegal.

Musk has yet to respond to Muddy Water’s offer.