WILMINGTON, Delaware, June 11 (Reuters) - Elon Musk made

billions of dollars by selling Tesla stock using

insider information, an institutional shareholder accused in a

lawsuit filed on Tuesday, asking the court to direct the Tesla

CEO to return "unlawful profits."

The lawsuit comes two days before a critical vote by Tesla

shareholders on whether to reinstate Musk's $56 billion pay

package, after a Delaware judge voided it in January because she

found that Musk had improperly controlled the process.

Musk and his brother, Kimbal Musk, a Tesla director, sold a

combined $30 billion in the electric vehicle maker's stock

between late 2021 and the end of 2022, cashing in before news

that would cause the stock to fall became public, according to

the lawsuit, which was filed by the Employees' Retirement System

of Rhode Island (ERSRI).

Musk sold the shares at artificially inflated prices by

concealing his plan to use the proceeds to buy social media

platform Twitter, which he later renamed X, according to the

lawsuit, filed at the Delaware Chancery Court. Musk also sold

Tesla stock when he knew that deliveries of Tesla cars had

fallen far below public projections, the lawsuit said.

Musk and Tesla did not respond to messages seeking a

comment.

The Employees' Retirement System of Rhode Island holds about

140,000 shares of Tesla. Tesla's stock closed at $170.66 on

Tuesday, valuing the stake at about $24 million.

A similar suit filed at the same court late last month by

Michael Perry, another Tesla shareholder, accused Musk of

insider trading when he sold over $7.5 billion of shares in

Tesla in late 2022.

Musk is in the middle of a regulatory probe to determine

whether he broke federal securities laws in 2022 when he bought

Twitter stock.

Tuesday's lawsuit by ERSRI also said that Musk had been

disloyal toward Tesla in several instances, including diverting

Tesla employees to work at X and causing Tesla to start paying

for advertising on Twitter after he bought the platform.

ERSRI was concerned that Tesla's board of directors was not

doing enough to oversee Musk's conflicts of interest, the fund's

general treasurer said in a statement.