Dan is an employee or the director/boss at Zangen.
Dan first appears in "The Locomotion Interruption" where he interviews Penny for a pharmaceutical sales representative’s position at Zangen as a favor to Bernadette. Penny realizes that the interview is not going well so she ends it and starts to leave. As a favor, she asks Dan not to tell Bernadette how badly she did because she is kind of scared of her. Dan says that he thought he was the only one who was scared of her. They start to bond noting that Bernadette is something of a bully. She has that squeaky little voice and Dan says that everyone else thinks she is SO nice. He had to cut one of Bernadette's research programs and was too scared of her to do it. They both agree not to tell her about the results of the interview. Later Bernadette is talking to Howard at home and tells him that it is hard to believe, but Penny got the job. She feels that it is because Dan really loves her.
Dan reappears in "The Champagne Reflection". where Penny makes Bernadette face up to her bullying ways in and Dan is still afraid of the latter when she yelled at him and his grandson after they lost the three-legged race at the company picnic. His grandson called her the mean kid with the big boobies. Bernadette is horrified when she realizes how everyone perceives her. Her father had taught her to not take any crap, and she can be even cruel with some of her comments without even knowing it. She thought she was the sweetest person she knew and should be in a tree baking cookies like a Keibler elf. She goes to apologize to Dan and finds out that due to everyone's fear of her, they were paying for her daily coffee even after the company stopped doing that (which they accomplished with a swear jar they keep for Bernadette's sake) and gave her a private toilet on her floor that was meant for everyone. She now feels like she has to leave the company and starts crying. Dan wants her to stop and promises to keep paying for her coffee and then ups it to getting her an espresso machine. Bernadette has found a new way to get what she wants.
- Dan reveals that he has an insulin pump when Penny talks about convincing obese people to have more cheesecake during her waitressing days. And based on his appearance, it's highly likely that he may suffer from Type 2 Diabetes.
- It's unknown what became of Dan's wife as he is not seen wearing a ring. This suggests that either Dan is a widower or divorced. The two of them still being married is also a possibility, as it's never mandated that a married couple HAS to wear rings.