UPDATE 2-KKR offers 40% premium to buy out Axel Springer minorities

* KKR, main shareholders looking to take company private

* Bid subject to 20% acceptance threshold

* Shares jump 13% in pre-market trading

* Springer issues profit warning (Writes through with quotes, context)

By Douglas Busvine

FRANKFURT, June 12 (Reuters) - Funds controlled by U.S. private equity investor KKR on Wednesday offered 63 euros a share to buy out minority shareholders in Axel Springer in a deal agreed with the German publisher's main shareholders.

The takeover offer, at a 40% premium, puts an equity value of 6.8 billion euros ($7.7 billion) on the business. It will be subject to reaching a minimum acceptance threshold of 20% of Springer's share capital, KKR and Springer said.

The offer is being launched in concert with the company's main shareholders, founder Axel Springer's widow Friede and CEO Mathias Doepfner, who want to take the firm private following a slide in the share price over the past year.

This buys time for the publisher of the influential Bild tabloid and financial news website Business Insider to prospect for acquisitions and build a digital classifieds portfolio that now earns more than four-fifths of its core profit.

"Axel Springer has undergone a successful period of digital transformation from which the company has emerged as a leading European digital powerhouse," said KKR's Philipp Freise.

"In light of the fast pace of change in the media sector, Axel Springer now needs continued organic investments and successful execution of its strategy," he said, adding that KKR would support this "in a long-term and sustainable manner".

Springer shares jumped by 13% in pre-market trade at broker Lang & Schwarz to trade at 63.45 euros, above the offer price. They rallied by 20% last week on news of the buyout plan before steadying to close at 56 euros on Tuesday.

"Our growth plans will require significant investment in people, products, technology and brands over the next years," said Doepfner. "The strategic partnership with KKR would enable us to pursue major growth opportunities by providing additional financial capabilities while relieving the mere focus on short-term financial targets."

Between them, Friede Springer - the fifth wife of company founder Axel Springer - and Doepfner control 45.4% of Axel Springer. Axel Springer's grandchildren, Axel Sven and Ariane, own a further 9.8% and are not party to the KKR deal.

The remaining 44.8% is in free float and is worth 3 billion euros ($3.4 billion) at the tender price. Subject to successful closing, Friede Springer and Doepfner would jointly control the company. Management would remain in place, KKR said.

PROFIT WARNING

Even as it disclosed the KKR buyout deal, Springer issued a profit warning, saying it saw a drop in revenue in the low single-digit percentage range this year. Its adjusted earnings before interest, taxation, depreciation and amortisation (EBITDA) face a mid-single-digit drop.

Looking ahead to 2020, the German publisher said its investment plans meant that adjusted EBITDA would be "significantly below" the current year, before an improvement expected in the ensuing years.

Investors had punished Springer shares over the past 12 months, sending them down by more than a quarter on perceptions that the company was overcommitted to its legacy media titles that have acted as a drag on its growing classifieds operation.

Springer also faces pressure from digital platforms such as Google that are sucking up advertising. Its jobs portal - Stepstone - has complained to the European Union over Google's recent launch of a jobs product in Germany that has grabbed a market lead overnight.

In bringing in KKR, Friede Springer, 76, has chosen a counterpart with a track record of long-term investments in the German media sector.

KKR, together with Permira, bought control of ProSiebenSat.1 Media in 2007 and sold out in 2014, having broadened the broadcaster's entertainment offering and launched a foray into e-commerce.

The private equity firm also entered a music rights joint venture with Bertelsmann in 2009, selling its stake back to the publisher four years later.

KKR said it was financing the offer primarily from its European Fund V. JPMorgan is acting as financial adviser, while UniCredit is providing financing. Its voluntary offer is subject to approval from the German financial regulator. ($1 = 0.8825 euros) (Reporting by Douglas Busvine, Editing by Sherry Jacob-Phillips and David Evans)