The Pancake Batter Anomaly - S1-E11
Continuity mistake: The way Penny holds her notepad when talking to Sheldon at the Cheesecake factory keeps changing instantly. (00:10:10)
The Habitation Configuration - S6-E7
Continuity mistake: When Wil first enters Fun with Flags, he has his flag partly on the table in front of him. In the next shot, the flag is not on the table at all.
The Comic Book Store Regeneration - S8-E15
Continuity mistake: While in Penny's apartment, Sheldon is folding laundry and Penny is talking to him from the kitchen counter. Between shots, the water bottle in front of Penny moves by itself to different spots on the counter.
The Retraction Reaction - S11-E2
Continuity mistake: Sheldon's formulae are written on three whiteboards. The marker color on the leftmost board is first red, later black. (00:07:05 - 00:09:21)
The Troll Manifestation - S8-E14
Continuity mistake: When the gang and Stephen Hawking are video chatting, the Android mascot is lying down when the camera is facing the gang, but when the camera is facing Stephen Hawking, the Android mascot is standing up.
The Bath Item Gift Hypothesis - S2-E11
Continuity mistake: Near the start, when the camera is on Raj, David Underhill is seen in the top left-hand corner of the screen shaking someone's hand, already in the cafeteria. Then, when the camera is on Wolowitz, David is just walking into the door of the cafeteria. David sits down to the right of the man sitting at the table, then shortly afterwards David is now sitting where the other guy was, originally.
The Griffin Equivalency - S2-E4
Continuity mistake: When discussing what qualities their new friend should have, the container Howard has changes position instantly. (00:17:20)
The Griffin Equivalency - S2-E4
Continuity mistake: When talking about wanting a griffin, the bottles and strip of paper on the table keep moving between shots. (00:16:00)
The Comic Book Store Regeneration - S8-E15
Continuity mistake: While Bernadette is talking with Howard about Stuart living in Mrs. Walowitz's home, she is taking items out of a grocery bag. One of the bags of food changes spots on the table in the next shot.
Continuity mistake: In "The Luminous Fish Effect" (S1E04) Sheldon tells Penny he weighs 140 pounds. In "The Porkchop Indeterminacy" (S1E16), he tells his sister he weighs 165. 25lbs difference would be a noticeable change, but he looks the same.
Suggested correction: Lying to Penny but not to his sister, not inconsistent with the characters and his relationships.
The Russian Rocket Reaction - S5-E5
Continuity mistake: Bernadette holds her wine glass in her left hand, holding it from the base of the glass; in the next shot she's drinking from her right hand holding the top of the glass and in the immediate next shot she's once more holding the glass from her left hand. (00:14:40)
The Einstein Approximation - S3-E14
Continuity mistake: When Sheldon is looking for another job, the woman is holding a piece of yellow paper up. Camera cuts and she is no longer holding the piece of paper.
Continuity mistake: In this episode Leonard has a snoring problem (a result of a deviated septum, which in all probability he was born with, plus Amy says Sheldon has always complained about Leonard's snoring, and Sheldon says after 5 or 6 years he's gotten use to Leonard's snoring), but in episode 14 of season 3 when Sheldon brings up snoring Penny says, "Leonard doesn't snore." And in episode 8 of season 6, Sheldon lists not snoring as one of Leonard's positive traits.
The Proton Displacement - S7-E7
Continuity mistake: During the jewelry-making session, when Penny is making a mess, there's a black piece stuck to her left hand. The piece is stuck on different parts of her hand throughout the scene. (00:07:15)
Continuity mistake: When Sheldon is sitting with Raj in his apartment watching television, the can of soda on the table in front of him rotates itself a couple of times. (00:14:40)
The Parking Spot Escalation - S6-E9
Continuity mistake: In this episode Penny mentions she has a sister ("I remember my first bikini wax. My sister did it with duct tape and melted Crayolas"), but in future episodes she has only a brother.
Suggested correction: While her brother was the only one that came to the wedding she mentions her many other times and never said she only had a brother. She mentions her father dancing with her and her water breaking at her wedding. She asks her dad about Randall and Lisa. She also mentions her sister "accidentally" shot her husband. So while the brother is more prominent the sister is mentioned throughout.
The Werewolf Transformation - S5-E18
Continuity mistake: When Penny is giving Sheldon his haircut, she accidentally shaves the back of his head. The clippers are going from the bottom of Sheldon's hair, up to the top of his head. When Sheldon goes to leave the room, it can be seen only four or five inches from the back of his head have been shaved off.
The Griffin Equivalency - S2-E4
Continuity mistake: In the opening scene, just after Howard says, 'Creepy good or creepy bad?', there is a shot where Howard is holding his food, even though Leonard hasn't given it to him yet and it isn't there in the shot before or after. After Leonard gives the food to Howard, the exact same shot is used after he says, 'I'm not necessarily talking about the food', so the shot was taken from there and it is shown twice. (00:00:25)
The Work Song Nanocluster - S2-E18
Continuity mistake: When Penny puts the box down at the start it is closed. Camera cuts and it's open instantly.
The Pancake Batter Anomaly - S1-E11
Continuity mistake: After Leonard gives Penny her pile of mail, she alternates from holding the pile by her side to at her front between each shot. (00:01:10)