Mark Cuban has a bone to pick with Donald Trump.

The billionaire investor and Shark Tank judge took to Twitter on Tuesday evening, where he criticized the Republican nominee for failing to release his tax returns and took aim at his management strategy. Cuban praised Hillary Clinton, the Democratic nominee, and husband Bill Clinton, citing their taxes as evidence that they are "much smarter business people and negotiators."

1) Lots of people concerned how much money the Clinton's have made. More interesting to me they have paid 43mm IN TAXES since 2007 -; Mark Cuban (@mcuban) July 26, 2016

2) I'd bet the 43mm in TAXES the Clinton's paid is not only more taxes than @realDonaldTrump has paid. I'd bet they made more too -; Mark Cuban (@mcuban) July 26, 2016

3) it's not a tough argument looking at their taxes and fec filings that the Clinton's are much smarter business people and negotiators -; Mark Cuban (@mcuban) July 26, 2016

4) I get offers almost daily (at same $ as clintons) to give speeches Organizations want knowledge and insight. It's a great business -; Mark Cuban (@mcuban) July 26, 2016

5) maybe @realDonaldTrump didn't release his taxes become @HillaryClinton paid more in taxes than @realDonaldTrump made in income ? -; Mark Cuban (@mcuban) July 26, 2016

6) here is a link for more details https://t.co/LEjkcKrp8A -; Mark Cuban (@mcuban) July 26, 2016

Cuban had previously suggested he would consider running as vice president to either Trump or Clinton.

For his part, Trump hasn't responded (at least not yet) on Twitter to Cuban's ruminations.