However, the same could not be said for R2-D2, who never had his memories erased. While there isn't a canonical reason for this decision, the likely explanation may have been that Threepio was more likely to say something he shouldn't have.
Did R2-D2 and C-3PO have their memories wiped in episode 3?
The two droids were dumped back on the streets, their memories wiped of the incident. Unlike R2-D2, Threepio's mind is wiped of all memories after the birth of Luke and Leia. Senator Bail Organa assigns C-3PO to duty aboard an Alderaanian diplomatic cruiser, serving under Captain Antilles.
He didn't recognize him because again, they all look the same & it was decades until he saw him again. There was no reason to believe he or R2 even existed anymore.
Finding C-3PO devoid of useful information, Bane and his accomplices kidnap R2-D2 and extract the vital data, before memory-wiping the droids of the incident, and letting them on their way.
C-3PO had his memories wiped after Episode III, but R2-D2 did not. However, they were working together on the same ship afterwards, where presumably, they would have conversations.
Darth Vader's true identity as Anakin Skywalker was a highly guarded secret, known only to a select few individuals including Palpatine, Obi-Wan Kenobi, Luke, Han, Leia, R2-D2, C-3PO, Master Yoda, Bail Organa, Ahsoka Tano, Darth Maul, Grand Moff Tarkin, Grand Admiral Thrawn, Jocasta Nu, Ferren Barr, Verla, Reva, ...
But Anakin remained staunchly against this idea for R2-D2, meaning the droid never had to worry about losing the memories of his past. As a result, R2-D2 could learn the value of intelligence, quick thinking and when and where not to speak up.
What's going on: Anthony Daniels, who plays the C-3PO role in all of the nine Skywalker saga films, recently told HuffPost that he wasn't sure why Obi-Wan Kenobi didn't know C-3PO. He said it's possible Obi-Wan knew too many droids.
secondly, in Legends, R2 was given programming that actually restricted him. from sharing any information with Luke or Leia. about their parents or relation to one another. this was all part of the plan. to conceal this information from the twins.
At the end of Star Wars: Episode III - Revenge of the Sith, C-3PO's memory was wiped, allowing him a fresh start by the time A New Hope begins, but R2-D2's memories remained intact, which is why many fans wonder why he didn't tell Luke the truth about his family history, but he might have not done that because he didn' ...
Darth Vader acts like he doesn't even know C-3PO or R2D2. They were with him since he was a child. He did everything he could to forget his past. Also, his plating had been replaced many times, and protocol droids all look very similar.
They aren't abbreviations — they're model and serial numbers. R2 is a second generation R-series astromech, serial number D2. * And C-3PO is a C-series protocol droid with the serial number 3PO.
However, one theory argues that Obi-Wan did recognize R2-D2, but he chose to pretend not to in order to avoid telling Luke the full truth. This would explain certain signs of familiarity between the Jedi and the droid and fit Obi-Wan's pattern of subtly lying to Luke.
The lack of recognition could have come from an old man simply not remembering the passing droids of his youth. Lastly, Owen didn't seem the sentimental type to form any emotional attachments to droids. Being a practical man, he viewed them as tools to be used and replaced when they no longer functioned.
Since Bail Organa had C-3PO's memory wiped previously in order to prevent him from spilling the secret of Leia's parentage, it could be that this was a semi-regular occurrence for the droid given he couldn't be trusted to keep quiet about things.
in the Dark Horse comic series star Wars Tales, which is now part of legends, it's revealed that Darth Vader did recognize C. 3PO on Cloud City. when 3PO was shot by Stormtroopers, his parts were brought before Vader. because the Imperials thought he could hold valuable.
3PO ended up in a cave (only his upper body was still intact), and he became a local legend known as "The Storyteller". Two young kids called Otalp and Remoh escaped their oppressors and visited 3PO, who told them the story of Luke Skywalker. Then the oppressive alien species showed up, and shot 3PO to death.
As has been noted in several instances, Artoo has never had a full memory wipe, enabling him to retain his recollections of everything he saw and heard over the decades. This includes his first meeting with Padme Amidala, a nine-year-old Anakin Skywalker, and C-3PO himself during the events of The Phantom Menace.
Unfortunately, Rex and Vader never meet again though. Why didn't Palpatine feel afraid of showing his evil actions, behaviors and ways to Anakin and the Jedi anymore?
