as Holder; Notice of Adverse Claim. (1) Delivery to a purchaser occurs when (a) He or a person designated by him acquires possession of a security; or (b) His broker acquires possession of a security specially indorsed to or issued in the name of the purchaser; or (c) His broker sends him confirmation of the purchase and also by book entry or otherwise identifies a specific security in the broker's possession as belonging to the purchaser; or (d) With respect to an identified security to be delivered while still in the possession of a third person when that person acknowledges that he holds for the purchaser; or (e) Appropriate entries on the books of a clearing corporation are made under Section 8320. (2) The purchaser is the owner of a security held for him by his broker, but is not the holder except as specified in paragraphs (b), (c) and (e) of subdivision (1) of this section. Where a security is part of a fungible bulk, the purchaser is the owner of a proportionate property interest in the fungible bulk. (3) Notice of an adverse claim received by the broker or by the purchaser after the broker takes delivery as a holder for value is not effective either as to the broker or as to the purchaser. However, as between the broker and the purchaser the purchaser may demand deliv- ery of an equivalent security as to which no notice of an adverse claim has been received.