No foreign equity is allowed in the practice of fishery profession, although foreigners may practice the profession subject to reciprocity. Fisheries is, however, not listed among the activities under the Annex on Professions of the 11th Foreign Investment Negative List where foreigners may practice through the corporate form. In this case, the reciprocity requirement that is concurred in the case of such profession may not apply to foreign corporate investments, cf. SEC-OGC Opinion No. 16-14, 23 May 2016, p. 3 ("[...] This means that the practice of profession by corporations should be done by 100% Filipino-owned corporations, as no foreign equity is allowed [...]). The Constitution, however, seems to allow firms with up to 40% foreign equity to explore, develop and use natural resources in lands of public domain, which include water and fisheries. Up to 40% of foreign equity is also allowed in the operation of deep sea commercial fishing vessels. As such, for the purposes of the OECD FDIRRI, it is assumed that most (if not all) aquaculture and fisheries activities are open to FDI up to 40% of foreign shareholding.
"Only the investment areas and/or activities listed in the attached Eleventh Regular Foreign Investment Negative List shall be reserved for Philippine nationals, subject to the exceptions and conditions indicated therein.
[...]
LIST A: FOREIGN OWNERSHIP IS LIMITED BY MANDATE OF THE CONSTITUTION AND SPECIFIC LAWS
No Foreign Equity [...]
2. Practice of Professions² (Art. XII, Sec. 14 of the Constitution, Sec. 1 of R.A. No. 5181, Sec. 7[j] of R.A. No. 8981), including Radiologic and x-ray technology (R.A. No. 7431), Criminology (R.A. No. 6506), Law (Art. VIII, Section 5 of the Constitution; Rule 138, Sec. 2 of the Rules of Court of the Philippines), and Marine deck officers and marine engine officers (R.A. No. 10635), subject to the Annex on Professions attached herewith and forming an integral part of this document, indicating the professions where (a) foreigners are allowed to practice in the Philippines subject to reciprocity; and (b) where corporate practice is allowed. Foreigners may teach at higher education levels (R.A. No. 8292), provided the subject being taught is not a professional subject (i.e., included in a government board or bar examination).[² Section 1(b) of Professional Regulation Commission Resolution No. 2012-668 defines 'practice of a profession" as an "activity/undertaking rendered by a registered and licensed professional or a holder of a Special Temporary Permit as defined in the scope of practice of a professional regulatory law."]
[...]
7. Utilization of marine resources in archipelagic waters, territorial sea, and exclusive economic zone as well as small-scale utilization of natural resources in rivers, lakes, bays, and lagoons (Art. XII, Sec. 2 of the Constitution)
[...]
Up to Forty Percent (40%) Foreign Equity [...]
16. Exploration, development and utilization of natural resources (Art. XII, Sec. 2 of the Constitution)7[7 7 Full foreign participation is allowed through financial or technical assistance agreement entered into with the President (Art. XII, Sec. 2 of the Constitution).]
22. Operation of deep sea commercial fishing vessels (Sec. 27 of R.A. No. 8550, as amended by R.A. No. 10654)
[...]
Annex on Professions
A. Foreigners are allowed to practice the following professions in the Philippines provided that their home country allows Filipinos to be admitted to the practice of these professions: [...]
-Fisheries (Section 27, PRC Resolution No. 2000-664)
[...]
B. Corporate practice is allowed in the following professions, subject to the requirements and conditions under the pertinent professional regulatory law: [...]
[fisheries not present in the list of professions in item B of this Annex][...]" (Eleventh Regular Foreign Investment Negative List (Executive Order No. 65 / 2018))
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"Section 2. All lands of the public domain, waters, minerals, coal, petroleum, and other mineral oils, all forces of potential energy, fisheries, forests or timber, wildlife, flora and fauna, and other natural resources are owned by the State. With the exception of agricultural lands, all other natural resources shall not be alienated. The exploration, development, and utilization of natural resources shall be under the full control and supervision of the State. The State may directly undertake such activities, or it may enter into co-production, joint venture, or production-sharing agreements with Filipino citizens, or corporations or associations at least sixty per centum of whose capital is owned by such citizens. Such agreements may be for a period not exceeding twenty-five years, renewable for not more than twenty-five years, and under such terms and conditions as may be provided by law. The State shall protect the nation's marine wealth in its archipelagic waters, territorial sea, and exclusive economic zone, and reserve its use and enjoyment exclusively to Filipino citizens." (Art XII, Section 2 1987 Constitution of the Republic of The Philippines)
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"Section 27. Persons Eligible for Commercial Fishing Vessel License. - No commercial fishing vessel license shall be issued except to citizens of the Philippines, partnerships or to associations, cooperatives or corporations duly registered in the Philippines at least sixty percent (60%) of the capital stock of which is owned by Filipino citizens. No person to whom a license has been issued shall sell, transfer or assign, directly or indirectly, his stock or interest therein to any person not qualified to hold a license. Any such transfer, sale or assignment shall be null and void and shall not be registered in the books of the association, cooperative or corporation. For purposes of commercial fishing, fishing vessels owned by citizens of the Philippines, partnerships, corporations, cooperatives or associations qualified under this section shall secure Certificates of Philippine Registry and such other documents as are necessary for fishing operations from the concerned agencies: Provided, That the commercial fishing vessel license shall be valid for a period to be determined by the Department."(Sec. 27, RA 8550)
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"The Ninth Regular Foreign Investment Negative List (FINL-9), pursuant to theConstitution and specific laws, provides, in List A, that no foreign equity is allowed for thepractice of professions, including real estate services, as such practice is limited to Filipinocitizens, save in cases prescribed by law. This means that the practice of profession bycorporations should be done only by 100% Filipino-owned corporations, as no foreignequity is allowed.
[...]
Based on the foregoing, we are of the view that no foreign participation is allowed incorporations, such as a real estate brokerage company, that will engage in the practice of realestate service.[...]" (SEC-OGC Opinion No. 16-14 Foreign Participation in a Real EstateBrokerage Company)

Eleventh Regular Foreign Investment Negative List (Executive Order No. 65 / 2018)
Art XII, Section 2 1987 Constitution of the Republic of The Philippines
RA 8550, Sec. 27
SEC-OGC Opinion No. 16-14 of 23 May 2016 on Foreign Participation in a Real Estate Brokerage Company
[<a href="https://www.officialgazette.gov.ph/downloads/2018/10oct/20181029-EO-65-RRD.pdf">List</a>],[<a href="http://www.officialgazette.gov.ph/constitutions/1987-constitution/">Constitution</a>],[<a href="http://www.lawphil.net/statutes/repacts/ra1998/ra_8550_1998.html">Act</a>],[<a href="https://www.sec.gov.ph/wp-content/uploads/2019/12/2016OpinionNo16-14.pdf">Opinion</a>]