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If you sell a patent to a related party (in this case the LLC), the income from this is all taxed as ordinary income. Since you anticipate controlling 80% of the LLC, it is a sale to a related party.Here is a piece from the IRS to help you see this:
This section discusses the rules that may apply to the sale or exchange of property between related persons. If these rules apply, gains may be treated as ordinary income and losses may not be deductible. See Transfers to Spouse in chapter 1 for rules that apply to spouses.
If a gain is recognized on the sale or exchange of property to a related person, the gain may be ordinary income even if the property is a capital asset. It is ordinary income if the sale or exchange is a depreciable property transaction or a controlled partnership transaction.
Depreciable property transaction. Gain on the sale or exchange of property, including a leasehold or a patent application, that is depreciable property in the hands of the person who receives it is ordinary income if the transaction is either directly or indirectly between any of the following pairs of entities.
A person and the person's controlled entity or entities.
A taxpayer and any trust in which the taxpayer (or his or her spouse) is a beneficiary unless the beneficiary's interest in the trust is a remote contingent interest; that is, the value of the interest computed actuarially is 5% or less of the value of the trust property.
An executor and a beneficiary of an estate unless the sale or exchange is in satisfaction of a pecuniary bequest (a bequest for a sum of money).
An employer (or any person related to the employer under rules (1), (2), or (3)) and a welfare benefit fund (within the meaning of section 419(e) of the Internal Revenue Code) that is controlled directly or indirectly by the employer (or any person related to the employer).
Controlled entity. A person's controlled entity is either of the following.
A corporation in which more than 50% of the value of all outstanding stock, or a partnership in which more than 50% of the capital interest or profits interest, is directly or indirectly owned by or for that person.
An entity whose relationship with that person is one of the following.
A corporation and a partnership if the same persons own more than 50% in value of the outstanding stock of the corporation and more than 50% of the capital interest or profits interest in the partnership.
Two corporations that are members of the same controlled group as defined in section 1563(a) of the Internal Revenue Code, except that "more than 50%" is substituted for "at least 80%" in that definition.
Two S corporations, if the same persons own more than 50% in value of the outstanding stock of each corporation.
Two corporations, one of which is an S corporation, if the same persons own more than 50% in value of the outstanding stock of each corporation.