Conn. Gen. Stat. § 42a-9-314: Perfection by control.

(a) A security interest in controllable accounts, controllable electronic records, controllable payment intangibles, deposit accounts, electronic documents, electronic money, investment property or letter-of-credit rights may be perfected by control of the collateral under section 42a-7-106, 42a-9-104, 42a-9-105a, 42a-9-106, 42a-9-107 or 42a-9-107a.

(b) A security interest in controllable accounts, controllable electronic records, controllable payment intangibles, deposit accounts, electronic documents, electronic money or letter-of-credit rights is perfected by control under section 42a-7-106, 42a-9-104, 42a-9-105a, 42a-9-107 or 42a-9-107a not earlier than the time the secured party obtains control and remains perfected by control only while the secured party retains control.

(c) A security interest in investment property is perfected by control under section 42a-9-106 not earlier than the time the secured party obtains control and remains perfected by control until:

(1) The secured party does not have control; and

(2) One of the following occurs:

(A) If the collateral is a certificated security, the debtor has or acquires possession of the security certificate;

(B) If the collateral is an uncertificated security, the issuer has registered or registers the debtor as the registered owner; or

(C) If the collateral is a security entitlement, the debtor is or becomes the entitlement holder.