In honor of the late Leonard Nimoy, who played Mr. Spock on both the big and small screen in Star Trek, Canadians have been scribbling his likeness on their $5 bills.

Spock Five-Dollar Bills

Using black pens, Star Trek fans have been altering the portrait of Canada’s seventh prime minister Sir Wilfrid Laurie on the $5 bills to look like the famed Vulcan. The doodlers, remembering Nimoy with his best-known character, are adding thicker eyebrows, his signature bowl cut and the illusion of pointy ears.

While the practice of drawing on the currency is not illegal, it’s heavily discouraged by the Bank of Canada.

“It is not illegal to write or make other markings on bank notes… However, there are important reasons why it should not be done,” said Bank of Canada spokeswoman Josianne Menard. “Writing on a bank note may interfere with the security features and reduces its lifespan. Markings on a note may also prevent it from being accepted in a transaction. Furthermore, the Bank of Canada feels that writing and markings on bank notes are inappropriate as they are a symbol of our country and a source of national pride.”

“Yes, it’s legal, but it’s just not a very nice or Canadian thing to do,” Menard had added in another statement.

Among the supporters of the #SpockingFives movement is NASA Administrator Charles Bolden. “Leonard Nimoy was an inspiration to multiple generations of engineers, scientists, astronauts, and other space explorers,”  Bolden said in a statement of support. “As Mr. Spock, he made science and technology important to the story, while never failing to show, by example, that it is the people around us who matter most.”