By virtue of the Foreign Exchange and Foreign Trade Act (FEFTA) and its implementing regulations, inward foreign direct investment is generally subject to an ex post reporting obligation. Submitting a prior notification is required for certain foreign investments in specified business areas or involving foreign nationals from specified countries. The specified business sectors include aircraft,  arms,  dual-use  technologies,  nuclear  energy,  space, electricity  utility,  gas  utility,  vaccine,  security  guard  and  telecommunications  and broadcasting services. Specific investment plans of non-residents and foreign-controlled enterprises in these sectors can be altered or suspended on the grounds of threat to national security, public order or public safety. 
"(Definitions)
Article 26(1)The term "foreign investor" means one of the following persons that undertakes inward direct investment or an equivalent action as set forth in the items of the following paragraph, or that makes a specified acquisition as prescribed in paragraph (3):
(i)an individual that is a non-resident;
(ii)a corporation or other organization established pursuant to foreign laws and regulations, or a corporation or other organization with a principal office in a foreign state;
(iii)a company in which the sum total of the number of votes held directly by persons as set forth in item (i) and (ii) (other than votes associated with shares that do not allow the holder to vote on all of the matters regarding which a resolution may be passed at a shareholders' meeting, but including votes associated with shares whose holders are deemed to hold voting rights pursuant to Article 879, paragraph (3) of the Companies Act (Act No. 86 of 2005); hereinafter the same applies in this item and item (iv) of the following paragraph) and the number of votes that Cabinet Order prescribes as being held indirectly through another company make up at least 50 percent of the number of votes of all shareholders or all members;
(iv)other than as set forth in the preceding two items, a corporation or other organization at which persons as set forth in item (i) constitute the majority of the officers (meaning directors or other persons equivalent thereto; hereinafter the same applies in this item) or the majority of the officers with representative authority.
(2)The term "inward direct investment or an equivalent action" means an action that falls under one of the following items:
(i)the acquisition of shares or equity in a company (other than through a transfer from a person as set forth in the items of the preceding paragraph, and other than the acquisition of shares in a company that has issued shares listed on a financial instruments exchange as defined in Article 2, paragraph (16) of the Financial Instruments and Exchange Act or shares that Cabinet Order prescribes as being equivalent thereto (referred to as a "listed company or its equivalent" in items (ii) and (iii) and the following paragraph));
(ii)the transfer of the shares or equity in a company other than a listed company or its equivalent that a person held prior to becoming a non-resident (but only a transfer from an individual that is a non-resident to one of the persons set forth in the items of the preceding paragraph);
(iii)the acquisition of shares in a listed company or its equivalent (but only if the number of shares in the listed company or its equivalent which are subject to the acquisition make up at least the proportion specified by Cabinet Order, and no less than 10 percent, of the total number of issued shares in that company; or if the sum total of the number of shares that the acquirer comes to hold in the listed company or its equivalent after the acquisition and the number of shares in that company held by non-resident individuals, corporations, and other organizations (but only those falling under a category of person as set forth in items (ii) through (iv) of the preceding paragraph) that are related to the acquirer through the holding of shares or any other such permanent economic affiliation or through kinship, as well as those held by any other person that Cabinet Order prescribes as being specially affiliated with the acquirer through equivalent ties, will make up at least the proportion specified by Cabinet Order, and no less than 10 percent, of the total number of issued shares in that company);
(iv)consent given for a substantial modification to a company's business purpose (if it is a stock company, this is limited to consent given by persons holding at least one-third of all shareholders' voting rights in that company);
(v)establishment of a branch office or other such place of business in Japan or substantial modification of the type or business purpose of a branch office or other such place of business in Japan (but only its establishment or modification as Cabinet Order prescribes, conducted by a person as set forth in item (i) or (ii) of the preceding paragraph);
(vi)the lending of money exceeding the amount that Cabinet Order prescribes to a corporation having its principal office in Japan (excluding lending by a person engaged in the banking business, lending in the course of trade by any other financial institution that Cabinet Order prescribes, and lendings made in Japanese currency by a person as set forth in item (iii) or (iv) of the preceding paragraph), for a term exceeding one year; [...]
(3)The term "specified acquisition" means the acquisition of shares or equity in a company other than a listed company or its equivalent, through a transfer by a person as referred to in the items of paragraph (1).
(Notification of Inward Direct Investment and Equivalent Actions; Recommendations to Modify the Substance Thereof; Related Matters)
Article 27(1)Before engaging in inward direct investment or an equivalent action (other than anything that Cabinet Order prescribes in consideration of an inheritance, testamentary gift, merger of corporations, or other circumstances; hereinafter the same applies in this Article) that Cabinet Order prescribes as being likely to fall under a category necessitating an examination under paragraph (3), a foreign investor, pursuant to Cabinet Order, must first file a notification of the business purpose of the inward direct investment or equivalent action, its amount, its timing, and any other information that Cabinet Order prescribes with the Minister of Finance and the competent minister for the business.
(2)A foreign investor that has filed a notification under the preceding paragraph with regard to inward direct investment or an equivalent action must not undertake in the inward direct investment or equivalent action that is the subject of that notification until the final day in the 30-day period that begins on the date that the Minister of Finance and the competent minister for the business accept the notification; provided, however, that on finding, before the end of this period, that, in light of its business purpose or any other consideration, the inward direct investment or equivalent action that is the subject of that notification does not fall under a category necessitating an examination pursuant to the following paragraph, the Minister of Finance and the competent minister for the business may shorten this period.
(3)When a notification under paragraph (1) has been filed, on finding it necessary to examine whether the inward direct investment or equivalent action that is the subject of that notification falls under one of the following categories of inward direct investment or equivalent action (referred to as "inward direct investment or an equivalent action that is a matter of national security or a similar concern" in paragraphs (4), (5), and (11)), the Minister of Finance and the competent minister for the business may extend the period during which the inward direct investment or equivalent action that is the subject of that notification must not be undertaken, but only to a period of four months beginning on the day on which the notification is accepted:
(i)inward direct investment or an equivalent action that is likely to cause one of the situations set forth in (a) or (b) (but only inward direct investment or an equivalent action that is undertaken by a foreign investor from a member state of a multilateral treaty or other international agreement on inward direct investment and equivalent actions that Cabinet Order prescribes and to which Japan has acceded (hereinafter referred to as a "treaty or other agreement" in this item), if there is no obligation to remove restrictions on that inward direct investment or equivalent action based on the treaty or other agreement; as well as inward direct investment or an equivalent action that is undertaken by a foreign investor from a state other than the member state of such a treaty or other agreement, if there would be no obligation to remove restrictions on the inward direct investment or equivalent action if the state in question were a member state of the treaty or other agreement):
(a)it would compromise national security, create a barrier to the maintenance of public order, or interfere with the preservation of public safety;
(b)it would have a significantly adverse impact on the smooth operation of the Japanese economy.
(ii)inward direct investment or an equivalent action that, because it is undertaken by a foreign investor from a state with which Japan has not concluded any treaty or other international agreement on inward direct investment and equivalent actions, it is found necessary to modify the substance of or to discontinue, in order to harmonize its treatment, in real terms, with the treatment of direct investment and equivalent actions that Japanese investors undertake in that state (meaning direct investment and equivalent actions that are equivalent to inward direct investment and equivalent actions as set forth in the items of paragraph (2) of the preceding Article);
(iii)inward direct investment or an equivalent action that it is found necessary to modify the substance of or to discontinue, as all or part of it constitutes a capital transaction for which, pursuant to Article 21, paragraph (1) or (2), persons have been placed under the obligation to get permission, based on the use of funds or anything else. [...]
(13)As regards anything equivalent to inward direct investment or an equivalent action that a person (this includes corporations and other organizations) other than a foreign investor undertakes on behalf of a foreign investor without using the name of the foreign investor, the person that is not a foreign investor is deemed to be a foreign investor and the preceding paragraphs and Article 29 apply.
(Notification of Specified Acquisition; Recommendations to Modify the Substance Thereof; Related Matters)
Article 28(1)Before seeking to make a specified acquisition (other than anything that Cabinet Order prescribes in consideration of an inheritance, testamentary gift, merger of corporations, or other circumstances; hereinafter the same applies in this Article) that Cabinet Order prescribes as being likely to fall under a category necessitating an examination under paragraph (3), a foreign investor, pursuant to Cabinet Order, must first file a notification of the business purpose of the specified acquisition, its amount, its timing, and any other information that Cabinet Order prescribes with the Minister of Finance and the competent minister for the business.
(2)A foreign investor that has filed a notification under the preceding paragraph with regard to a specified acquisition must not undertake the specified acquisition that is the subject of that notification until the final day in the 30-day period that begins on the date that the Minister of Finance and the competent minister for the business accept the notification; provided, however, that on finding, before the end of this period, that, based on the business purpose or any other consideration, the specified acquisition that is the subject of that notification does not fall under a category necessitating an examination under the following paragraph, the Minister of Finance and the competent minister for the business may shorten this period. [...]
(8)As regards anything equivalent to a specified acquisition that a person (this includes corporations and other organizations) other than a foreign investor undertakes on behalf of a foreign investor without using the name of the foreign investor, the person that is not a foreign investor is deemed to be a foreign investor and the preceding paragraphs and the following Article apply.
(Ordering Measures)
Article 29(1)In the following cases, if the Minister of Finance and the competent minister for the business find that the inward direct investment or equivalent action in question falls under a category of inward direct investment or equivalent action as referred to in Article 27, paragraph (3), item (i) (limited to inward direct investment or an equivalent action that is likely to cause a situation that would compromise national security; hereinafter referred to as "inward direct investment or an equivalent action that is a matter of national security" in this Article), they may order the foreign investor that has undertaken the inward direct investment or equivalent action to dispose of all or part of the shares or equity acquired through the inward direct investment or equivalent action or take other necessary measures, pursuant to Cabinet Order, after hearing the opinion of the Council on Customs, Tariffs, Foreign Exchange, and Other Transactions; and if they find that the specified acquisition in question falls under the category of a specified acquisition that is a matter of national security, they may order the foreign investor that has undertaken the specified acquisition to dispose of all or part of the shares or equity acquired through the specified acquisition or take other necessary measures, pursuant to Cabinet Order, after hearing the opinion of the Council on Customs, Tariffs, Foreign Exchange, and Other Transactions:
(i)if a foreign investor that must file a notification under Article 27, paragraph (1) or paragraph (1) of the preceding Article undertakes inward direct investment or an equivalent action or a specified acquisition without filing that notification;
(ii)if a foreign investor that has filed a notification under Article 27, paragraph (1) or paragraph (1) of the preceding Article undertakes the inward direct investment or equivalent action or the specified acquisition that is the subject of that notification, before the end of the period prohibiting that undertaking.
[...]
(Report of Inward Direct Investment or an Equivalent Action)
Article 55-5(1)Having undertaken inward direct investment or an equivalent action (other than anything that Cabinet Order prescribes in consideration of an inheritance, testamentary gift, merger of corporations, or other circumstances; hereinafter the same applies in this Article), a foreign investor, pursuant to Cabinet Order, must report the substance of the inward direct investment or equivalent action, its timing, and any other information that Cabinet Order prescribes to the Minister of Finance and the competent minister for the business; provided, however, that this does not apply to inward direct investment or an equivalent action for which a notification must be filed pursuant to Article 27, paragraph (1). [...]" (Foreign Exchange and Foreign Trade Act (No. 228 of 1949), last amended by Act No. 38 of 2017, Articles 26, 27, 28, 29 and 55-5 [google translation])
Foreign Exchange and Foreign Trade Act (No. 228 of 1949), last amended by Act No. 38 of 2017, Articles 26, 27, 28, 29 and 55-5
[<a href="https://www.japaneselawtranslation.go.jp/en/laws/view/3267">Act</a>]