Mark Hamill is breaking some hearts, but also trying to help his fans not get taken advantage of by those selling fake autographs.

The Star Wars: The Force Awakens star took to Twitter Sunday night and one at a time told fans whether their merch bearing his signature was legit.

"I'm so sorry there's so many fans spending their hard-earned money for fraudulent signatures," Hamill said in a tweet.

Of course, there were some pieces Hamill really did sign through the years; he told fans to look at those examples to see exactly how he signs his name.

Hamill reprises his iconic role as Luke Skywalker in the latest, record-breaking installment of the space adventure series.

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Hamill's tweets to fans, pointing out real and fake signatures, are listed below:

In a word- NO. I'm so sorry there's so many fans spending their hard-earned money for fraudulent signatures. #FAKE https://t.co/717Bv02ASA

—Mark Hamill (@HamillHimself) December 27, 2015

That one is REAL- go for it! (but only at a reasonable price!) #Authentic https://t.co/SxZw59MDti

—Mark Hamill (@HamillHimself) December 28, 2015

Sadly, another fake. Look at the signatures I verified to learn to spot the forgeries for yourself. #BeatTheDealers https://t.co/HFndM0Al1Z

—Mark Hamill (@HamillHimself) December 28, 2015

Memorize this REAL signature and you can start spotting the phonies yourself! #BeatTheDealers https://t.co/yB0aVXY74E

—Mark Hamill (@HamillHimself) December 28, 2015

It's REAL- Congratulations! (And glad you liked the movie!) #CBTM #BeatTheDealers https://t.co/qYFCdZi4L5

—Mark Hamill (@HamillHimself) December 28, 2015

All REAL!!! #BeatTheDealers https://t.co/GYVtxaToOf

—Mark Hamill (@HamillHimself) December 28, 2015

Because I owe it to all true fans to protect them from being victimized by dishonest dealers! #FightFraud #FansRule https://t.co/aXk6zBMCAs

—Mark Hamill (@HamillHimself) December 28, 2015