Nissan and Renault on Wednesday finalized the terms of their revamped alliance, with the Japanese automaker committing to invest up to 600 million euros ($663 million) in its partner’s electric vehicle unit Ampere.

This agreement puts the two automakers on a more equal footing and caps months of sometimes tense negotiations over intellectual property sharing in the future.

Nissan (NSANF) has invested in Ampere as a strategic investor and will hold a board seat in the new company.

Ampere could be valued at up to 10 billion euros, according to sources. The Nissan investment of up to 600 million euros in Ampere would be about 6%, lower than the 15% Nissan had flagged as a maximum share in February.

According to Nissan Chief Executive Makoto Uchida, the Ampere investment “complements and strengthens Nissan’s electric push in Europe.”

A completion date of the overhaul has not been set yet, but it is expected to be completed by the fourth quarter of 2023, if all regulatory approvals have been received.

This deal confirms Renault’s (RNLSY) commitment to reduce Nissan’s stake from around 43% to 28.4% by transferring Nissan shares into a French trust, putting both automakers on an equal footing.