The phrase "a proprietary formula" is correct and usable in written English.
You can use it when referring to a unique recipe, method, or process that is owned and protected by a company or individual.
Example: "The company has developed a proprietary formula for its skincare products that sets them apart from competitors."
Alternatives: "a patented formula" or "an exclusive formula".
Tempur-Pedic uses a proprietary formula made of viscoelastic material, which is based on a substance developed by NASA.
The value estimates are based on public records and other data using "a proprietary formula," according to Zillow.
They combined a radioisotope called yttrium-90 with a proprietary formula that prevents the compound from traveling beyond the tumor.
Multicentre, randomised, comparative, clinical evaluation of a low-calorie diet alone or supplemented with a proprietary formula in healthy overweight subjects.
Each has a proprietary formula that generally includes various herbs, roots, flowers and spices, which are macerated in alcohol, sometimes blended with a sweet syrup and tempered in barrels or bottles.
To form the signature Birkenstock foot bed, the latex and the cork are blended in a proprietary formula, creating a brownish granulated paste that, in its prebaked state, bears an unfortunate visual resemblance to cat vomit.
The commercially fixatives tested included Cell-Block (Bio-Optica, Italy), as a Glyoxale - Ethyl Alcohol fixative; RCL2, a French proprietary formula based on Acetic Acid, Ethyl alcohol and non-reducing Carbohydrates (Celbio, Italy).
He portrayed the announcement last week that the company would hand $32 billion to its shareholders in a special dividend this year as proof of the success of Microsoft's proprietary formula -- instead of a sign that the company had matured and run out of growth opportunities, as some analysts suggested.
On Fox News, Shepard Smith asked Jackson, "How in the world are we just figuring out this dispersant is toxic after we have put millions of gallons of it into the Gulf of Mexico?" The following day, BP argued in a letter that only one alternative existed in sufficient quantity, and that the company was unable to acquire the proprietary formula for evaluation in so short a time.
The Halliburton attorney shrugged off the inquiry, stating that "When you talk about a complete list of ingredients, you're getting fairly deep into the proprietary formula itself".
Think of the proprietary formula for Coca Cola, or the patents protecting blockbuster drugs in the pharma industry.
