(a) On and after July 15, 1991, there is exempted from the taxes imposed by this part an amount equal to an amount that is attributable to a 1/4 percent rate of tax with respect to the following:

1. (1) The gross receipts from the sale of and the storage, use, or other consumption in this state of the following:

   1. (A) Tangible personal property if the seller is obligated to furnish or the purchaser is obligated to purchase, the property for a fixed price pursuant to a contract entered into prior to July 15, 1991.
   2. (B) Materials and fixtures obligated pursuant to an engineering construction contract or a building construction contract entered into for a fixed price prior to July 15, 1991.
   3. (C) For purposes of this section, tangible personal property shall not be deemed obligated pursuant to a contract for any period of time for which any party to the contract has the right to terminate the contract upon notice, whether or not the right is exercised.
2. (2) A lease of tangible personal property that is a continuing sale of the property for any period of time for which the lessor is obligated to lease the property for an amount fixed by the lease prior to July 15, 1991. For the purposes of this paragraph, the sale or lease of tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not that right is exercised.
3. (3) The possession of, or the exercise of any right or power over, tangible personal property under a lease that is a continuing purchase of the property for any period of time for which the lessee is obligated to lease the property for an amount fixed by a lease entered into prior to July 15, 1991. For purposes of this paragraph, the storage, use, or other consumption of, or possession of, or exercise of any right or power over, tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not the right is exercised.

(b) From July 15, 1991, to the date on which the taxes imposed by Sections 6051.2 and 6201.2 cease to be operative pursuant to subdivision (b) of Section 6051.2 or subdivision (b) of Section 6201.2, there is exempted from the taxes imposed by this part an amount equal to an amount that is attributable to a one-half of 1 percent rate of tax with respect to the following:

1. (1) The gross receipts from the sale of and the storage, use, or other consumption in this state of the following:

   1. (A) Tangible personal property if the seller is obligated to furnish or the purchaser is obligated to purchase, the property for a fixed price pursuant to a contract entered into prior to July 15, 1991.
   2. (B) Materials and fixtures obligated pursuant to an engineering construction contract or a building construction contract entered into for a fixed price prior to July 15, 1991.
   3. (C) For purposes of this section, tangible personal property shall not be deemed obligated pursuant to a contract for any period of time for which any party to the contract has the right to terminate the contract upon notice, whether or not the right is exercised.
2. (2) A lease of tangible personal property that is a continuing sale of the property for any period of time for which the lessor is obligated to lease the property for an amount fixed by the lease prior to July 15, 1991. For the purposes of this paragraph, the sale or lease of tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not that right is exercised.
3. (3) The possession of, or the exercise of any right or power over, tangible personal property under a lease that is a continuing purchase of the property for any period of time for which the lessee is obligated to lease the property for an amount fixed by a lease entered into prior to July 15, 1991. For purposes of this paragraph, the storage, use, or other consumption of, or possession of, or exercise of any right or power over, tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not the right is exercised.

(c) From July 15, 1991, to the date the taxes imposed by Sections 6051.5 and 6201.5 cease to be operative, there is exempted from the taxes imposed by this part an amount equal to an amount that is attributable to a 1/2 percent rate of tax with respect to the following:

1. (1) The gross receipts from the sale of and the storage, use, or other consumption in the state of the following:

   1. (A) Tangible personal property if the seller is obligated to furnish or the purchaser is obligated to purchase, the property for a fixed price pursuant to a contract entered into prior to July 15, 1991.
   2. (B) Materials and fixtures obligated pursuant to an engineering construction contract or a building construction contract entered into for a fixed price prior to July 15, 1991.
   3. (C) For purposes of this section, tangible personal property shall not be deemed obligated pursuant to a contract for any period of time for which any party to the contract has the right to terminate the contract upon notice, whether or not the right is exercised.
2. (2) A lease of tangible personal property that is a continuing sale of the property for any period of time for which the lessor is obligated to lease the property for an amount fixed by the lease prior to July 15, 1991. For the purposes of this paragraph, the sale or lease of tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not that right is exercised.
3. (3) The possession of, or the exercise of any right or power over, tangible personal property under a lease that is a continuing purchase of the property for any period of time for which the lessee is obligated to lease the property for an amount fixed by a lease entered into prior to July 15, 1991. For purposes of this paragraph, the storage, use, or other consumption of, or possession of, or exercise of any right or power over, tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not the right is exercised.

(d) On and after July 15, 1991, there is exempted from the taxes imposed by this part an amount equal to the tax imposed by this part on July 14, 1991, with respect to the sale or purchase of any tangible personal property that was exempt prior to the enactment of the act adding this section, with respect to the following:

1. (1) The gross receipts from the sale of and the storage, use, or other consumption in the state of tangible personal property if the seller is obligated to furnish or the purchaser is obligated to purchase, the property for a fixed price pursuant to a contract entered into prior to July 15, 1991.
2. (2) A lease of tangible personal property that is a continuing sale of the property for any period of time for which the lessor is obligated to lease the property for an amount fixed by the lease prior to July 15, 1991. For the purposes of this paragraph, the sale or lease of tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not that right is exercised.
3. (3) The possession of, or the exercise of any right or power over, tangible personal property under a lease that is a continuing purchase of the property for any period of time for which the lessee is obligated to lease the property for an amount fixed by a lease entered into prior to July 15, 1991. For purposes of this paragraph, the storage, use, or other consumption of, or possession of, or exercise of any right or power over, tangible personal property shall be deemed not to be obligated pursuant to a contract or lease for any period of time for which any party to the contract or lease has the unconditional right to terminate the contract or lease upon notice, whether or not the right is exercised.