David Lamas said thieves at Buffalo Bayou broke into his truck and inadvertently stole a binder Tuesday afternoon.
Lamas says the suspects drove away in a sedan.
The binder contained one of his "I Love Selena" license plates.
Lamas' has traveled the Western Hemisphere with the plate in hand, sharing the late singer's message of love.
He's even documented his adventures on Instagram.
Lamas said people from across the world have stopped and asked him about the plate.
"I was gone for three minutes," said Lamas. "I hope that they are not a Selena fan, and they don't know what they have," he said.
Lamas filed a report with the Houston Police Department. He hopes someone will contact him on social media if they come across the vanity plate.