As used in this chapter the following words shall have the meaning indicated:

(1) The term "professional service" means any type of personal service to the public which requires as a condition precedent to the rendering of such service the obtaining of a license or other legal authorization and which prior to the passage of this chapter and by reason of law could not be performed by a corporation, including, but not by way of limitation, certified public accountants, chiropractors, dentists, osteopaths, physicians, podiatric physicians and surgeons, chiropodists, architects, veterinarians and attorneys-at-law.

(2) The term "professional corporation" means a corporation which is organized under this chapter for the purpose of rendering professional service.

(3) The term "ineligible person" means any individual, corporation, partnership, fiduciary, trust, association, government agency, or other entity which for any reason is or becomes ineligible under this chapter to own shares issued by a professional corporation. The term includes a charitable remainder unitrust or charitable remainder annuity trust that is or becomes an ineligible person for failure to comply with subsection (5)(b) of this section.

(4) The term "eligible person" means an individual, corporation, partnership, fiduciary, qualified trust, association, government agency, or other entity, that is eligible under this chapter to own shares issued by a professional corporation.

(5) The term "qualified trust" means one of the following:

(a) A voting trust established under RCW 23B.07.300, if the beneficial owner of any shares on deposit and the trustee of the voting trust are qualified persons;

(b) A charitable remainder unitrust as defined in section 664(d)(1) of the internal revenue code or a charitable remainder annuity trust as defined in section 664(d)(2) or 664(d)(3) of the internal revenue code if the trust complies with each of the following conditions:

(i) Has one or more beneficiaries currently entitled to income, unitrust, or annuity payments, all of whom are eligible persons or spouses of eligible persons;

(ii) Has a trustee who is an eligible person and has exclusive authority over the share of the professional corporation while the shares are held in the trust, except that a cotrustee who is not an eligible person may be given authority over decisions relating to the sale of shares by the trust;

(iii) Has one or more designated charitable remaindermen, all of which must at all times be domiciled or maintain a local chapter in Washington state; and

(iv) When distributing any assets during the term of the trust to charitable organizations, the distributions are made only to charitable organizations described in section 170(c) of the internal revenue code that are domiciled or maintain a local chapter in Washington state.