Fender has widened its legal campaign over the design of its iconic Stratocaster electric guitar, sending Yamaha a cease-and-desist notice as it seeks to stop rival manufacturers selling similar instruments in Europe.

Yamaha confirmed it received the letter in May and is reviewing the notice while considering how to respond.

Neither company has disclosed which guitars were named, although Yamaha’s long-running Pacifica range is widely considered the most likely target due to its resemblance to the Stratocaster’s double-cutaway body shape.

The Pacifica (pictured) launched in 1990, 36 years after Fender introduced the Stratocaster, and has since become one of Yamaha’s best-known electric guitar ranges.

Fender’s legal campaign follows a German court ruling that granted copyright protection to the Stratocaster body shape across the European Union.

The case involved Chinese manufacturer Yiwu Philharmonic Musical Instruments, which did not appear to defend the proceedings. Critics have argued the resulting default judgment did not fully test Fender’s copyright claim.

Fender has since sent notices to manufacturers and retailers including PRS Guitars, LsL Instruments and German retailer Thomann, which sells Stratocaster-style guitars through its Harley Benton brand.

Thomann has launched its own legal action against Fender, arguing the dispute could affect competition, product diversity and the future of guitar manufacturing.

Fender’s iconic Stratocaster guitar, released in 1954

Fender said protecting its designs was part of its responsibility as steward of the brand and the legacy associated with its instruments.

“We remain open to engaging constructively with partners and companies across the industry,” Fender said.

The company has faced criticism from musicians and smaller guitar builders who argue the Stratocaster shape has become a generic industry design after decades of widespread use.

The dispute is currently centred on Europe. Fender unsuccessfully sought US trademark protection for the Stratocaster body shape in 2009 and did not appeal the decision.

Yamaha’s involvement significantly raises the stakes, with the Japanese company regarded as the world’s largest musical instrument manufacturer and well placed to challenge Fender’s claims in court.