Animal rights organization People for the Ethical Treatment of Animals is using the stock market to further its cause by buying shares in companies it believes are mistreating animals.

PETA has shares in more than 70 companies, and buys the minimum amount of stock needed to submit shareholder proposals for a vote at their annual meetings. It’s a strategy PETA plans to employ Wednesday, as it submits a statement to SeaWorld Entertainment Inc.’s SEAS, -1.11% annual meeting from PETA representative and pro-surfer Kelly Slater.

PETA’s holdings range from SeaWorld to pharmaceutical, food, retail and biotechnology companies, including names like McDonald’s Corp. MCD, -1.03% , General Electric Co. GE, -2.41% and Lululemon Athletica Inc. LULU, -2.75% .

“We choose to act as a shareholder only as necessary, If the company is not making forward progress on animal welfare issues.” said Stephanie Shaw, corporate affairs specialist at PETA.

To be eligible to submit a proposal, a shareholder must own at least $2,000 in market value, or 1% of a company’s shares. The shareholder has to hold on to that stock for at least one year before submitting a proposal and must hold the shares through the meeting, according to the Securities and Exchange Commission.

PETA began filing shareholder resolutions around 1987 and started with the manufacturers of cosmetics and household cleaners that did testing on animals.

“This is a strategy that has paid off for PETA,” Shaw said.

“ “All the ads in the world won’t change what the public now knows to be true,” Kelly Slater, PETA representative and pro-surfer ”

Shaw said last week a PETA representative spoke at the Lululemon meeting about a resolution asking for the company to refrain from selling down jackets filled with feathers it says are plucked from live birds.

Lululemon referred to a filing from the meeting which shows the proposal was not approved.

PETA has also spoken out against McDonald’s for its treatment of animals that are raised for meat.

“We certainly have a long history of shareholder activism with McDonald’s,” Shaw said.

Part of PETA’s tactic is to submit questions and resolutions with “graphic descriptions,” which Shaw said is to educate management and shareholders. If the company addresses and makes progress on the actions, PETA will often withdraw its proposal before the meeting.

Typically, PETA buys the shares itself, but it also can get shares through donations from members.

The amount of time PETA holds on to the stock varies, Shaw said. PETA will sell the stock if it is having “constructive dialogue” with the company and the company is taking actions on PETA concerns.

Surfer Kelly Slater has submitted a statement on behalf of PETA at SeaWorld’s annual meeting Getty Images

An outspoken critic of SeaWorld, PETA first purchased SeaWorld shares when it went public in 2013. It purchased shares again in 2014 when the SeaWorld stock dipped so that PETA would continue to have enough of a stake to submit proposals.

SeaWorld’s stock has lost 39% since its first day of trading on April 19, 2013.

At the annual board meeting, which is online only, Slater will submit a question criticizing SeaWorld’s treatment of animals--a subject that has plagued the company since the Blackfish documentary premiered--and asking when the company will relocate the animals to a seaside sanctuary.

In response to the killer whale mistreatment allegations, SeaWorld started a print, television ad campaign highlighting its proper care of the animals as well as a social media question and answer campaign.

But PETA says the ads are spreading misinformation.

“All the ads in the world won’t change what the public now knows to be true: that the company imprisons highly intelligent, emotionally complex, social animals in tiny, barren concrete tanks, which leads to aggression and disease,” Slater’s statement says.

At last year’s meeting, PETA had actress Jessica Biel submit a question.

SeaWorld said it “sets the highest standard of care for killer whales in the zoological community” and added “PETA owns stock and is entitled, like any other shareholder, to pose a question.”