TeslaChief Executive Elon MuskFrom Nov. 19 through Nov. 29, last year, 5,044,000 shares of the most highly valued automaker in the world were donated to a charity. The filing was made with U.S. Securities and Exchange Commission on Monday.

Based on closing prices for Tesla shares during the five days he gave the stock, the donation was valued at $5.74 trillion.

It did not include the name of charity in the filing.

The billionaire, who polled Twitter users to determine if he wanted 10% off his stake in the electric car maker, sold shares worth $16.4 billion.

Last year, he tweeted that he’d pay $11 Billion in taxes due to the expiration of his stock options.

Also, he had a scuffle with Elizabeth Warren and Bernie Sanders who both called for rich people to pay higher taxes.

Analysts claim that Musk would receive a tax benefit by giving Tesla stock to charity. Donating shares to charity does not result in capital gains tax.

He would enjoy a huge tax savings. Bob Lord, an associate fellow of the Institute for Policy Studies, who studies tax policy said that he could save anywhere from 40% to 50% of $5.7 billion in income tax.

Musk could have given the stock to intermediaries like “donor-advised fund” and not to charity groups, he stated.

Tesla could not be reached immediately for comment.

Musk’s public acts of philanthropy have been slower than those made by other billionaires. Musk Amazon.comFounding founder Jeff BezosThey have given less than 1% from their net worth. Warren BuffettAnd George SorosForbes reports that more than 20% had been given away as early September.

Musk established the Musk Foundation in 2001. The foundation offers grants for “development of safe AI to benefit humanity”, among other causes. Musk’s foundation is worth more than $200 million.

Musk’s foundation gave $100 million prizes last year for those who came up with technology to remove carbon from our atmosphere. Last year, Musk said he donated $20 million for schools in Cameron County Texas (where a Space X rocket launch facility is situated) and $10 million for the City of Brownsville.

Musk also has flirted with loftier philanthropic goals. Musk tweeted last year, “If (the United Nations World Food Programme can explain… how $6 billion will solve global hunger, then I will sell Tesla stock immediately and do it!”

Musk responded to David Beasley’s plea for donations.

Last January, he asked users on Twitter about ways to give money that actually makes a difference. (It’s a lot harder than you think).