From Canon USA:
Thank you for using Canon products.
It has come to our attention that there are instances of counterfeit EF 50mm f/1.8 II lenses for digital SLR cameras being brought into Canon service centers for repair. These counterfeit products have neither been designed nor manufactured by Canon, yet they fraudulently display the Canon logo and other Canon trademarks, and, as illegal products, they infringe on Canon Inc.'s trademark rights. Canon has taken a strong stance in eradicating these counterfeit products which infringe on the intellectual property rights of our company.
While the exterior of the counterfeit EF 50mm f/1.8 II lens elaborately imitates the exterior of the genuine lens, the parts and electric circuits used inside the counterfeit lens are different from the those used inside the genuine lens. As such, these counterfeit products do not satisfy the safety standards of various countries and the safety/quality standards of Canon. Please note that Canon cannot be held liable for any malfunction, phenomena, damage or injury that occurs due to the use of these counterfeit products, so please exercise caution when making your purchase.
We truly appreciate your continued patronage of Canon products.
See below for the differences between genuine and counterfeit products that have been confirmed as of now and that can be identified by customers.
Please review the location of the Company Name on the mount with the lens cap removed as indicated in the image below.
There is a space between “CANON” and “INC.”
The company name is shown in either printed or molded letters (two types exist).
There is no space between “CANON” and “INC.”
If you have not already done so, please register your Canon Product. By registering, we will be able to notify you via email about future announcements.
This information is for residents of the United States and its five territories only. If you do not reside in the USA or its five territories, please contact the Canon Customer Support Center in your region.
Customer Support Operations
Canon U.S.A., Inc