Merck KGaA is continuing its quest to foil the merger plans of US electronic materials producer Versum with compatriot Entegris and buy Versum itself.

The German pharmaceuticals and chemicals producer said it has commenced its $48 per share cash tender offer for all outstanding shares in the Arizona-based firm.

The offer, which is without interest and less any withholding taxes, reflects an enterprise value for Versum of around $6 billion and an EBITDA multiple of around 13.3 times the 2018 figure, Merck said. Both the offer and withdrawal rights are scheduled to expire at 5 p.m. Eastern Daylight Time on June 7, 2019, unless the offer is extended.

Further to its filing of a proxy statement with the US Securities and Exchange Commission announced earlier, Merck said it has begun mailing its “definitive proxy materials,” including a green proxy card. In its second open letter to Versum shareholders, it stressed that it is “firmly committed” to completing the acquisition, and the tender offer is “an unambiguous step toward that objective.”

The Darmstadt-based group said it has entered into a facilities agreement with Bank of America Merrill Lynch, BNP Paribas Fortis and Deutsche Bank, which provides it with “fully committed financing” for the proposed deal.

Merck told Versum shareholders it is approaching them directly as the company’s board refuses to engage, despite its offer being “unquestionably superior to the proposed Entegris transaction.” An analysis by Versum’s own financial advisor, Lazard, supports that view, it said.

Additionally, Merck said the premium valuation reflected its tender offer is “certain and immediate,” without any of the significant ongoing integration, operational or market risks reflected in the value of the Entegris stock consideration and without the need for the achievement of synergies.

The German group also that its offer carries no conditions other than the redemption of Versum’s poison pill and other customary conditions for offers of this type.

“The regulatory process is underway, and we expect that regulatory clearances will be received in a timely manner,” Merck said. At the same time, it took a jab at the Versum board, calling its recently revised synergy estimates “illusory” and “a transparent attempt to catch up to the value of our superior proposal.”

In a repeated attempt to ward off the hostile takeover attempt, Versum said it had identified incremental cost and revenue synergies in the deal with Entegris, the amount of which was more than double that announced at the time of the original proposal.