The Chimpanzee beneficiaries of Sandy’s undersea treedome are paying a visit to see what progress she has made with her inventions. But Sandy doesn't think any of her work will satisfy the chimps, and if they don’t like what she’s invented Sandy could lose her funding forcing her to leave Bikini Bottom. SpongeBob and Patrick decide to help their distraught friend by taking over her work and finishing her inventions. At first, Patrick has ideas of things that have already been invented, such as a pencil and a mirror (which ironically is actually a parallel universe). After hours of hard work, SpongeBob and Patrick invent a back scratching, hair-combing, nose-picking ukulele-tuner. When the Chimps arrive, Lord Reginald is the first to test it (though never wanted to, as Patrick forced him). Shockingly, the invention works, but when tuning the ukulele, the machine malfunctions, hits Reginald with the ukulele, slaps him, then starts attacking him with all sorts of weapons. Meanwhile, Sandy hears the screaming of Reginald, and arrives just as the machine spits out Reginald. The Chimps decide to close down the Treedome, but when Dr. Marmalade holds out a banana, Sandy's "nutcracker" peels it for him. It is revealed that this is an invention that Chimps have been searching hundreds of years for. Soon they decide to let Sandy stay for 20 more years, including a higher salary. After the Chimps leave, Patrick decides to test out the machine that injured Reginald, which, of course, malfunctions on him, yet he still yells out "All right!"
The back scratcher that SpongeBob buys in the beginning of the episode costs him 52 box tops.
This is the first time Goofy Goober is referenced outside of the movie.
Sandy will be able to remain in Bikini Bottom for 20 more years, before her next expiration on October 23, 2026. However, in the movie which is set in the year 2030, she is still in Bikini Bottom. One possible explanation is that she was visiting or she got a renew for her contract.
This is the first episode to have actual land mammals in it besides Sandy, Mermaid Man, and Barnacle Boy.
Based on the comparative size of SpongeBob and Patrick when compared to the humans depicted in The SpongeBob SquarePants Movie, the monkeys depicted in this episode would only be 2 - 3 inches tall.
The monkeys have been searching for the banana-peeling nutcracker since 1889.
After Sandy's song ends, SpongeBob and Patrick start crying just like in Texas.
The things holding SpongeBob's invention together:
Screws driven into bottle caps
Pieces of tape made into an X
A taped down lollipop
Chewed bubble gum
The phrase on SpongeBob's invention says "Dr. Professor Patrick Rulez!" However the invention was finished before Patrick started calling himself "Mr. Dr. Prof. Patrick".
The towns for those that have nowhere else to go, as mentioned by the bus driver, in which the bus makes stops to:
SpongeBob's invention is called "The Automatic Back-Scratcher, Hair-Comber, Nose-Picker and Ukulele-Tuner 9000".
The peanut SpongeBob talks to says, "It's dark in here".
The inventions Patrick thinks of:
Pencil: (A stick that can be used to draw or write stuff with)
Light bulb: (A glass ball that lights up so the user can see in the dark)
When Sandy sings her "birds that fly upon the ground" line, a manta ray swims by, releasing a bird call. This is strange, because most birds are depicted as scallops.
Patrick often insultingly refers to SpongeBob as an "unpaid intern" in this episode. Strangely, he is perfectly fine with actually being an unpaid intern (and referred to as so) in Bummer Vacation.
When SpongeBob talked to Patrick about the his mouth moved before the reflection.
In Sandy's song, you can hear string squeaks camouflaged in the background of her music. Although in "Texas ", you can hear that the guitar strumming sounds distorted, so the string squeaks can't be heard.
Running Gag: Patrick wants people to call him "Mr. Dr. Prof. Patrick".
In Greek, this episode is called Έρχονται οι πίθηκοι which means The ape's are coming.
During the title card, the music is the same as in the episode title card, Selling Out.
This episode title is a parody of Chips Ahoy!, a popular cookie snack.
Christopher Ryan, Rik Mayall and Nigel Planer are best known for their roles as Mike, Rick and Neil on The Young Ones (TV series).
The helmet Sandy invented is similar in style and design to the helmet worn by Noodle, fictional guitarist for Gorillaz, an American rock band, during Phase 1.
Lord Reginald appears to be a parody and resemblance of Cranky Kong from the Donkey Kong Country series.
The chimps arrive in a yellow submarine. This is a possible reference to the Beatles song Yellow Submarine.
The Hasbro toy, Barrel of Monkeys, appears on the title card.
An element of this episode, Sandy's funding potentially being cut, bears similarities to the Mystery Science Theatre 3000 episode "Laserblast", in which Dr. Clayton Forrester's funding is cut, forcing him to disconnect the Satellite of Love and leaving Mike Nelson and the Bots to what Dr. Forrester thinks will be an eventual demise.
When SpongeBob looks in the mirror, he is wearing his water helmet, but in the mirror it is gone.
If you look at Sandy playing her guitar, you see she's playing with her left hand. However, in other episodes like Band Geeks, she plays with her right.
When the machine spits out Lord Reginald, he is bald from the accident. But when Professor Percy says to invent the Poop Thrower, Lord Reginald 's hair is all grown back.
When SpongeBob and Patrick say "It's here!", captions say "It's Eric!"
Sandy said in the beginning of the episode that the chimps were coming that afternoon. When SpongeBob and Patrick want to help, they work all night, and the chimps come the next day.
At one moment, Sandy is not in her breathing suit.