Nielsen top shareholder WindAcre Partnership has stepped up its campaign against the $28 per share takeover offer from two private equity firms, saying the data analytics company’s stock can reach $80 per share within three years.

WindAcre, which owns more than 27% of Nielsen, argued in a Tuesday presentation that the company has a “world class business” with an intrinsic value of $52 per share today and a “credible path” to $80 per share by 2025.

Nielsen shares closed down 1.7% Tuesday at $26.31 each, giving the company a market value of $9.5 billion.

WindAcre said the $28 per share offered by Evergreen Coast Capital — the private equity arm of U.S. activist hedge fund Elliott Investment Management — and Brookfield Asset Management, isn’t “even close” to Nielsen’s “fair value.”

“We believe that Nielsen has an unmatched capability here to solve the hardest problem in media,” WindAcre Managing Partner Snehal Amin said on a conference call Tuesday. “We believe the advertisers know that. That’s what they want, and at the end of the day, they are the ones that will decide.”

Amin explained that markets are currently undervaluing Nielsen because of the ongoing “significant product and business transformation.” He listed several catalysts that will drive the stock, including an expected media-rating council re-accreditation and the launch of Nielsen One.

Achieving an average annual revenue growth of 4% will allow Nielsen to distribute $3 a share in cash to shareholders in 2023, which can grow to $4.50 over the next decade, Amin argued. He added that another level the company can pull to lift the stock is taking on more debt to fund share repurchases.

“We’ve always believed there are billions of dollars on the table here, and that’s why we fought so hard for a better deal for all shareholders than the deal we have before us today,” Amin said.

Before coming out in opposition to the buyout earlier this month, WindAcre is said to have offered its support to Elliott and Brookfield in exchange for $1.1 billion in additional equity. The bidders refused that proposal and WindAcre upped its holding to 27.6%, from 9.6%, a stakebuilding that triggered an investigation in the U.K., where Nielsen is incorporated.

WindAcre has also taken steps to block the deal, including by filing a motion seeking to prevent a delisting by anyone holding less than 75% of Nielsen’s outstanding shares.