The cemetery and its owners
The sale of the Jewish cemetery to the municipality of Porz

In November 1942 the synagogue municipality of Zündorf was dissolved by the district court of Cologne and its property was transferred to the Reichsvereinigung of Jews.
The district office Rhineland offered the Jewish cemetery of Zündorf on December 16th 1942 to the purchase to the municipality of Porz.  
  The municipality of Porz wrote on January 14th 1943 that they were ready to buy the area of 3.700 square meters for 740,00 RM. Further they asked to execute the act by the notary Witthoff in Cologne-Deutz.
Though, the closure of the contract was put off, because the approval of the supervisory authority was not given. Due to the activities of the imperial security main office which prohibited the work of the Reichsvereinigung of Jews in June, 1943. Thus the upper finance president of the city of Cologne was used as a governor of the cemetery property.  
  On January 20th 1944 the procedure of purchase was initiated again, and the upper finance president informed the mayor of the city of Porz in a letter that he is now able to sell the property to them with the approval of the imperial minister of finances which he still would have to check on. Though a registration must be renounced, because they'd have to wait until the property of the RVdJ has transfered to the German empire, but is still able to sale the property to the municipality of Porz.20.
On February 2nd 1944 the upper finance president of the city of Cologne affirmed his authority for the sales of the cemetery to the mayor of Porz. Again the notary Gustav Witthoff from Cologne-Deutz was suggested for the sales contract to be signed at.  
  Thus tax bailiff Erich Reuter appeared on March 23rd 1944, as a representative for the German Reich, and Mr. Otto Schmidtmann, a notary functioned as a representative of the municipality of Porz. They didn't have the power of representation to execute the contract before the notary public.
The property went over to the municipality of Porz, however, no change occurred in the land register because the signature of the mayor was missing.  

The retransfer of the Jewish cemetery to the Cologne synagogue municipality

The British military government ordered on October 20th 1947 that the Jew's cemetery should be returned to the synagogue municipality in Cologne free of charge. In 1946 already the tax office Cologne-north tried to draw the municipality of Porz into ownership for the property, so they would have to pay the real estate transfer tax. The local government appealed first that files were missing and ignored further writings. Also the settlement center for imperial property vainly tried to make the municipality of Porz pay. Finally, the county Rhein-Berg was asked to interfere and make Porz pay the tax or else change the ownership structures. The municipality of Porz let go several requests without any reaction. On the 9/30/1948 the county Rhein-Berg sent a second reminder which gained first positive results, as the municipality of Porz had been asked to report about the reasons of abduction of information at the same time: On 6/10/1948 they did not get all information, but dismissed a renter who had used the cemetery area "for many years" as grassland. The county Rhein-Berg told Porz on 4/4/1949 to transfer back the area of the graveyard to the synagogue municipality of Cologne. On the second reminder from the 4/26/1949 the municipality of Porz had to tell the head of the district authority of Rhein-Berg that they have never owned of the Jewish cemetery at all: the notary public's contract had not been signed by the mayor, so that a conveyance didn't occur.

On 5/18/1946 the tax office Cologne-north demands the municipality of Porz to the payment of the land transfer tax on [StA Porz]  
  16/14/1946: The municipality of Porz writes to the tax office Cologne-north that files were missing. [StA Porz]
10/17/1947: The settlement center for property of the III. Reich in Wahn wants a real estate transfer tax to be paid, [StA Porz  
  5/14/1948: The synagogue municipality of Cologne wants to know about the condition the graveyard is in. [StA Porz]
6/9/1948: The municipality of Porz answers the request.[StA Porz]  
  9/30/1948: County Rhein-Berg duns the city of Porz for the second time to give information to them [StA Porz]
10/6/1948: The municipality of Porz gives
information to the county Rhein-Berg about the possession relations [StA Porz]
  10/6/1948: The municipality of Porz dismisses the baker J. Platz who used the Jewish cemetery as grassland. [StA Porz]
4/4/1949: The county Rhein-Berg demands a retransfer of the Jewish graveyard by the municipality of Porz [StA Porz]:

"The execution of my demands is expected immediately..."

  5/3/1949: The municipality Porz confirms to the County Rhein-Berg, they have never been the owner of the graveyard because the contract never came into effect. [StA Porz]

A collection of sources about the sales and retransfer of the Jewish graveyard can be found here.