A broker-dealer registered under the Securities Exchange Act of 1934, who has not previously had any certificate denied or revoked under this law or any predecessor statute, shall be exempted from the provisions of Section 25210 if he has no place of business in this state and he does not direct offers to sell or buy into this state in any manner to persons other than broker-dealers, banks, savings and loan associations, trust companies, insurance companies, investment companies registered under the Investment Company Act of 1940, pension or profit-sharing trusts (other than self-employed individual retirement plans), or other institutional investors or governmental agencies or instrumentalities designated by rule of the commissioner, or to more than 15 other customers (whether or not self-employed individual retirement plans) having an existing account with such broker-dealer prior to any offer made to them in this state, during any period of 12 consecutive months, whether or not the offeror or any of the offerees is then present in this state.