Migliaccio & Rathod LLP is investigating whether Canon is using firmware updates to impair third-party RF-mount lenses, forcing consumers to purchase more expensive Canon-branded options.

Reported Issues

Users report that Canon firmware updates have disabled autofocus or otherwise broken compatibility with lenses from Viltrox, Sigma, Tamron, and others—after purchase. Canon has also restricted licensing of the RF mount, despite early marketing implying openness.

Why Consumers Should Be Concerned

If firmware updates degrade compatibility to steer consumers toward Canon’s higher-priced lenses, this may constitute unfair trade practices, false advertising, and potentially antitrust tying.

Signs You May Be Affected

Own an RF-mount body with affected third-party lenses
Experienced loss of functionality after firmware updates
Paid more for Canon lenses due to compatibility restrictions

If affected, fill out the form below or contact [email protected].

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Your name Your phone number Your email State of Residence What is the name of the affected product or service? When did you last purchase this product or service (month and year)? Do you have proof of purchase (receipt, email confirmation, transaction on your bank statement, etc.)?

Please briefly describe the issue with the product or service and when it occurred.

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