As I stated in one of the comments on the Superheroes and Identity Irresponsibility post, Matt Murdock has had a hell of a time keeping his secret identity intact. Here is a list of all the various moments that his secret identity has been compromised.
Way back in Daredevil #17 (June, 1966), Daredevil and Spider-Man teamed up. Unfortunately, this came back to bite Matt in Daredevil #24, when Spider-Man sent a letter to Nelson & Murdock telling Matt that he’s figured out he’s Daredevil and that he’s secret is completely safe. Unfortunately, this being a letter, it was instead read by Foggy Nelson and Karen Page.
This caused Matt to immediately reveal that no, no, it’s not him that’s Daredevil, it’s actually his twin brother Mike. He actually went on with this charade for a while before “killing” Mike. He attempted to stay away from being Daredevil, but eventually started up again, explaining that Mike must have trained someone else before he “died.”
Samuel “Starr” Saxon was a robotics expert that eventually become the second Mister Fear and then went full on robot and became the Machinesmith (whom Captain America once described as “like the internet, but more evil”). Before all that, though, he was an enemy of Daredevil and sent a robot named “the Plastoid” to kill him. The Plastoid used “aromagraphs” (basically scent fingerprints) to track its prey, so it was able to find Matt in his secret identity and even after he defeated it, Saxon was able to track down where the Plastoid went and figured out that Matt was Daredevil.
Daredevil fought Saxon as Mister Fear a few more times before Saxon accidentally fell to his death...at which point his robots downloaded his consciousness into a robot body and he became the Machinesmith. It’s unknown if the Machinesmith still remembers Matt’s secret identity or not.
Matt finally revealed his secret identity to Karen Page in Daredevil #58 with the full intention of both retiring from being Daredevil and marrying Karen. Unfortunately, he couldn’t do the first and so Karen left him. Eventually, Karen ended up moving to Los Angeles to try and become an actress.
Unfortunately, as revealed during Frank Miller and David Mazzaucchelli’s seminal storyline “Born Again,” what she became was a drug addict. And so in Daredevil #227, this happens:
This led to the Kingpin, Wilson Fisk, learning Matt’s secret identity and exploiting it, first getting him disbarred and then trying to kill him. With the help of Karen, Foggy, Ben Urich, and Captain America, however, Matt was able to not only survive, but beat the Kingpin at his own game. However, Fisk was still left with the knowledge of Matt’s secret identity.
A little while later, in the story arc “Fall from Grace” (Daredevil #319-#325) some tabloids threatened to publish rumors that Matt was actually Daredevil, so in order to protect Foggy and Karen, Matt faked his own death. (This would actually be the second time he faked his death.) This then led to him getting a new identity as “Jack Batlin” (yes, it does sound very, very fake) and a new costume that was red and black with armor.
Yes, this was the ‘90s, the era of grim and gritty and extremeness and that included Daredevil. I especially like the metal shoulder pads, because of course Daredevil would wear shoulder pads in the ‘90s. Everyone was wearing them.
Eventually, Matt was able to clear up all the rumors about being Daredevil and discarded the armored costume for his normal red one. And everyone breathed a sigh of relief and decided from then on never to talk about this except in the context of “How weird was the ‘90s?”
In 1998, Daredevil’s comic was relaunched as part of “Marvel Knights,” which eventually resulted in the long, well-regarded run of Brian Michael Bendis and Alex Maleev. Their first story arc together was called “Underboss” and it was about a civil war in the Kingpin’s organization — and it ended with one of the Kingpin’s men running to the FBI, unwilling to give up Fisk, but willing, instead, to give up Daredevil’s secret identity.
This, then, led to Daredevil #32, “Out,” where someone at the FBI leaks the secret to the press and it’s published on the front page. Matt publicly denied it and sued all of the newspapers who published it, but it was still out there.
In fact, this reveal would be much harder to shake than any of the rest. From now on, Matt Murdock would be seen as “That lawyer who might be Daredevil” and he wouldn’t be able to get rid of that reputation.
Matt fought for the longest time to make his secret identity secret again...so why reveal it? Well, during Mark Waid’s run, Daredevil fought against the Sons of the Serpent, who had managed to infiltrate the New York justice system, putting their own members as lawyers and judges. They then told Matt that if he didn’t go along with their plan, they would reveal everything about him, including his secret identity, with such evidence that he wouldn’t be able to deny it.
So in Daredevil #36, Matt called himself to the stand, took the oath, and then admitted to being Daredevil in order to stop the Sons of the Serpents. The fact that he was not only Daredevil, but had also repeatedly lied to the press and the public caused the Bar Association to disbar him. So he moved out to San Francisco, where he was also licensed to practice law, and left his secret identity behind. Eventually, he even changed his costume to be a snazzy suit and tie (although he quickly changed back to the regular red devil suit in the end).
And that was the end of his secret identity troubles. Everyone knew he was Daredevil, so there was no denying it.
Well, that is until the All-New, All-Different Marvel, where Matt suddenly had his secret identity back and only Foggy Nelson knew his secret. Why? How? We have yet to find out.