TRESPASS AND INSURANCE 1155 



is that, by the patent, the pubhc is fully apprised of the invention, and after 

 the expiration of the 17-year exclusive period, the public has the benefit of 

 the invention. This explains why the laws are somewhat stringent as to 

 adequacy and completeness of the disclosure in the patent specification. 

 For this reason, the specifications of a patent constitute an excellent refer- 

 ence and source of information. 



In the field of geophysics there has been considerable patent activity. 

 A large number of patents have been granted on methods and apparatus. 

 Many of these early patents have now expired, but improvements in meth- 

 ods and apparatus continuously form the subject matter of new patents. 



In the allied arts, such as electronics, wave recording and photography, 

 there is a vast maze of patents. Many of these are used in geophysical 

 exploration and instrumentation. In the field of geophysics itself, the 

 general policy among those obtaining patents has been to license the same 

 for use upon payment of royalty or other compensation. 



There have been very few situations in which any considerable number 

 of relatively important geophysical patents were collected by any one 

 owner.* Probably the largest single collection of related patents in the 

 field of seismic prospecting was acquired by the Texaco Development 

 Corporation. Texaco has made these patents available by licensing them 

 either on a paid-up basis, depending upon the number of crews operating, 

 or on a running royalty basis. This policy and program became generally 

 effective after a preliminary legal skirmish in 1934. 



At that time the Texas Company brought a patent infringement suit against the 

 Sun Oil Company in the District Court of the United States for the Southern District 

 of Texas, at Houston. This suit was based upon three patents assigned to the Texas 

 Company. 



The first was on an invention of Dr. Ludger Mintrop, of Germany, and related to 

 a process for testing and exploring geological structures. He applied for United States 

 Letters Patent in 1920 and was granted Patent No. 1,599,538, entitled "Geological 

 Testing Methods," on September 14, 1926. 



A second patent, obtained on an application of Dr. Burton McCollum, of Wash- 

 ington, D.C., related to a process and apparatus for determining the slope of subsurface 

 rock boundaries. He filed his application in 1923, and Patent No. 1,724,495, entitled 

 "Method and Apparatus for Determining the Slope of Subsurface Rock Boundaries," 

 was granted on August 13, 1929. 



The third patent, also obtained upon an invention of Dr. McCollum, concerned a 

 process and apparatus for studying subsurface contours. This application was filed in 

 1923, and Patent No. 1,724,720, entitled "Methods and Apparatus for Studying Sub- 

 surface Contours," was granted on August 13, 1929. 



Since the life of a United States Patent is seventeen years from the date of grant, 

 these three patents have now expired, but at that time they were in effect and formed 

 the nucleus of a large-scale program initiated by the infringement suit mentioned. 



In the complaint The Texas Company alleged that it and its predecessors in title 

 had spent large sums of money in exploiting these patents, which had proved to be 

 very successful, and asserted that the Sun Oil Company had willfully infringed the 

 patents. The complaint prayed for an accounting and payment of profits and damages, 



* C. R. Hrdlicka, "Summary of Some Pending Patent Litigation Relating to Seismic Explora- 

 tion," Geophysics, Vol. I, No. 1, Jan., 1936. 



