A House Pseudonym is a Pen Name that can be used by any writer at a given publisher.
House Pseudonyms have been used to disguise that a long series has become a Franchise Zombie by allowing other authors to use the creator's name. They have been used to make a collaborative work look like it came from a single author, using a name that belongs to neither of the actual writers.
In the internet age, some websites use them as well. It may be a conscious decision, or it may be the byproduct of giving a standard moniker to posters who aren't signed into the site.
- Hajime Yatate is a collective pseudonym for the Sunrise staff.
- Izumi Todo (best known for her work on Pretty Cure) is the pseudonym for Toei Animation.
- Moriyama Ayako is the pseudonym for the Irodori studio of Kemono Friends fame, that came from an independent anime they made years earlier..
- In-universe: in Little Witch Academia (2017), "Annabel Crème", author of the 365-volume Night Fall novel series (an obvious sendup of Twilight), is revealed to be just the pseudonym of at least 13 (and counting) witch authors as of the anime's beginning, although in this case the name is handed down to a successor instead of used simultaneously for a whole circle of ghostwriters, making it overlap with Legacy Character. It becomes a minor plot point when Lotte is offered to write the latest sequel and in so doing become the next Annabel (the current one is a tiny 12- or 13-year-old, despite "Annabel" supposedly having written the series continuously for 120 years). The current Annabel never reveals her real name though.
- Martha Marcy May Marlene has a sort-of in-universe example: All of the cult members must give their name as either "Marlene Lewis" or "Michael Lewis", depending on their gender, when they answer the phone.
- Carolyn Keene of the Nancy Drew novels and Franklin W. Dixon of The Hardy Boys novels. Notable due to the fact that both series has lasted long enough that you have to apply a serious dosage of Comic-Book Time to even pretend to believe in the house pseudonyms. The writing careers of Carolyn Keene and Franklin W. Dixon span more than eight decades. If they were real people, they'd have to be well over a hundred years old by now.
- K. A. Applegate of Animorphs, retroactively. There is a real K. A. Applegate, but she left the series about halfway through to work on other projectsnote while a string of ghostwriters kept it alive.
- Victor Appleton of the Tom Swift books, and Victor Appleton II of the Tom Swift, Jr. books.
- Maxwell Grant of the Shadow novels (usually Walter B. Gibson, but also Theodore Tinsley, Bruce Eliott and on one occasion Lester Dent).
- Kenneth Robeson of the Doc Savage novels (usually Lester Dent).
- Inverted with Harry Potter. Due to the great complexity of the series, several readers thought it was the work of multiple authors; however, J.K. Rowling rebuked those claims by stating it was indeed just her, much to the awe of this disbelieving side of the fanbase.
- Erin Hunter. When starting Warrior Cats, they decided to use a pen name because there were two main writers and they wanted to avoid having the books on two different shelves. Later, the pseudonym expanded as HarperCollins added other authors and editorial teams working on similar animal-focused series (Seekers, Survivors, and Bravelands).
- James Axler of the Deathlands series and its spinoff, Outlanders
- Dr. Haha Lung: Author of a large number of books on war, martial arts, and ninjutsu such as Mind Control: The Art of Psychological Warfare. Due to the similar content and writing style of the books, for a time, this was suspected to be a pseudonym of Ashida Kim but he has denied it and has stated that Haha Lung is a house name used by Citadel Press, a former publisher of his books with whom he had a falling out years ago. He has also pointed out that Lung is a Chinese word for "dragon" and combining with the name Haha suggests "laughing dragon" (as in "Ha Ha") so this pseudonym is probably intentionally meant to be a pun of sorts. Kim has been taking issue with Citadel on what he perceives as theft of intellectual property and denial of royalties on past books published with this firm. He notes that the material in most of Lung's books is identical to the material in the books he published with the same company.
- Jack Mckinney: Author of the Robotech novels. Actually consists of James Luceno and the late Brian Daley. After Daley's death, Luceno would write three additional Robotech novels using the pseudonym.
- Dungeons & Dragons has had Richard Awlinson, of the Forgotten Realms "Avatar" trilogy (the first two were Scott Ciencin, the final one was Troy Denning), and T.H. Lain of the "Iconics" novels (nine different authors). According to an article in Dragon, the thinking behind this was getting all the books in a series shelved together in bookstores.
- MAD has several pen names that are used by various contributors, such as "J. Prete".
- "Anonymous Coward" at Slashdot.
- "Anonymous" at 4chan. Related is Anonymous, the well-known "hacking" group. The one with the question mark and suit logo.
- Toshiaki of Futaba Channel.
- SiIvaGunner contributors who wish to remain anonymous have the artist information on their songs read "Barney Rubble" on the albums (in keeping with the channel's The Flintstones theming). Highest Quality Rips Volume FOUR HOURS! instead uses "Principal Seymour Skinner" (as the album chronicles the channel's Continuity Reboot, which substituted The Simpsons for The Flintstones).
- WOR radio in New York created the character of Martha Deane during The Great Depression as a fictional Granny Classic who hosted a daily show giving domestic tips and conducting interviews, and several women played the role. The most popular one, Mary Margaret McBride, gradually gave up the pretense of the character (even admitting that she was in her 40s and didn't even have children, let alone grandchildren), and when she left to do network radio she continued under her own name. A later Martha Deane, Marion Young Taylor, played the role for over three decades, and adopted the persona full-time. When she died the character was basically retired.
- KILT in Houston started the Hudson & Harrigan show, one of the first "morning zoo"-type Top 40 radio programs in 1967. A few years later the duo quit, but wanting to keep the brand going, KILT hired at least two other pairs to take the roles of "Hudson" and "Harrigan" over the years. The show ended up running until 2010.