1

IN THE UNITED STATES DISTRICT COURT

FOR THE EASTERN DISTRICT OF TEXAS

WACO DIVISION

APPLIANCE COMPUTING III, INC.

d/b/a SURFIELD

Plaintiff,

v.

REDFIN CORPORATION,

Defendant.

§

§

§

§

§

§

§

§

§

§

Case No. 6:20-cv-00376-ADA

DEFENDANT REDFIN CORPORATION’S ANSWER TO COMPLAINT

I. NATURE OF THE ACTION

1. Redfin admits that the complaint concerns allegations of infringement of United 

States Patent Nos. 9,836,885; 10,102,673; 10,510,111; and 10,592,973. Redfin denies all other 

allegations of Paragraph 1.

II. PARTIES

2. Redfin is without sufficient information to admit or deny the allegations of 

Paragraph 2, and on that basis, Redfin denies all allegations of Paragraph 2.

3. Redfin admits that it is a corporation organized and existing under the laws of the 

State of Delaware. Redfin admits that it maintains a place of business at 4030 West Braker 

Lane, Building 5, Suite 510, Austin, Texas 78759. Redfin admits that National Registered 

Agents, Inc., 1990 Bryan Street, Suite 900, Dallas, Texas 75201-3136 is its registered agent for 

service of process in the State of Texas. Redfin denies all other allegations of Paragraph 3.

III. JURISDICTION AND VENUE

4. Redfin admits the factual allegations of Paragraph 4.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 1 of 13
2

5. Redfin denies that it resides in the Western District of Texas. Redfin denies that it 

has “committed acts of infringement in this judicial district.” Redfin admits that it maintains 

regular places of business in the Western District of Texas. Redfin denies all other allegations of 

Paragraph 5 that it has not specifically admitted.

6. Redfin admits that it has places of business in Austin, Texas; San Antonio, Texas; 

Frisco, Texas; and Houston, Texas. Redfin denies all other allegations of Paragraph 6.

IV. FACTS

A. Redfin’s Founding

7. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 7, and on that basis, Redfin denies all allegations of Paragraph 7.

8. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 8, and on that basis, Redfin denies all allegations of Paragraph 8.

9. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 9, and on that basis, Redfin denies all allegations of Paragraph 9.

10. Redfin admits that in July 2006 Redfin received the Innovator of the Year award 

from Inman News. Redfin is without sufficient information to admit or deny any other allegation 

of Paragraph 10, and on that basis, Redfin denies all allegations of Paragraph 10 that it has not 

specifically admitted.

B. David Eraker’s Intellectual Property Contributions To Redfin

11. Redfin admits the allegations of Paragraph 11.

12. Redfin is without sufficient information to admit or deny any allegation of

Paragraph 12, and on that basis, Redfin denies all allegations of Paragraph 12.

13. Redfin admits the allegations of Paragraph 13.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 2 of 13
3

14. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 14, and on that basis, Redfin denies all allegations of Paragraph 14.

15. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 15, and on that basis, Redfin denies all allegations of Paragraph 15.

16. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 16, and on that basis, Redfin denies all allegations of Paragraph 16.

17. Redfin denies all allegations of Paragraph 17.

18. Redfin admits the allegations of Paragraph 18.

19. Redfin admits the allegations of Paragraph 19.

20. Redfin admits the allegations of Paragraph 20.

C. Surefield’s Patented 3D Rendering Technology

21. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 21, and on that basis, Redfin denies all allegations of Paragraph 21.

22. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 22, and on that basis, Redfin denies all allegations of Paragraph 22.

23. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 23, and on that basis, Redfin denies all allegations of Paragraph 23.

24. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 24, and on that basis, Redfin denies all allegations of Paragraph 24.

25. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 25, and on that basis, Redfin denies all allegations of Paragraph 25.

26. Redfin admits that Mr. Eraker is stated as a named inventor of United States 

Patent No. 9,836,885. Redfin admits that Mr. Eraker is stated as a named inventor of United 

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 3 of 13
4

States Patent No. 10,102,673. Redfin admits that Mr. Eraker is stated as a named inventor of 

United States Patent No. 10,510,111. Redfin admits that Mr. Eraker is stated as a named 

inventor of United States Patent No. 10,592,973. Redfin denies all other allegations of 

Paragraph 26.

27. Redfin admits that each of U.S. Patent Nos. 9,836,885; 10,102,673; 10,510,111; 

and 10,592,973 is entitled “Image-Based Rendering of Real Spaces.” Redfin denies all the 

claims of each of U.S. Patent Nos. 9,836,885; 10,102,673; 10,510,111; and 10,592,973 are valid. 

Redfin is without sufficient information to admit or deny any other allegation of Paragraph 27, 

and on that basis, Redfin denies all allegations of Paragraph 27 that it has not specifically 

admitted.

28. Each of the Patents-In-Suit speaks for itself. Redfin need not admit or deny the 

allegations of Paragraph 28.

29. Redfin admits that the specification of each of U.S. Patent Nos. 9,836,885; 

10,102,673; 10,510,111; and 10,592,973 states “have not eliminated the need to physically go to 

the property to understand how it is laid out.” Redfin admits that the specification of each of 

U.S. Patent Nos. 9,836,885; 10,102,673; 10,510,111; and 10,592,973 states “without physically 

visiting the property to look at it, the property can only be seen from the viewpoint of the 

photographer and the lack of spatial navigation.” Redfin denies all allegations of Paragraph 29 

that it has not specifically admitted.

30. Redfin denies all allegations of Paragraph 30.

31. Redfin admits that the specification of each of U.S. Patent Nos. 9,836,885; 

10,102,673; 10,510,111; and 10,592,973 states “in an attempt to allow the viewer to have more 

control over what he can observe, some real estate websites have used panorama cameras to take 

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 4 of 13
5

panoramic photos of the properties.” Redfin admits that the specification of each of U.S. Patent 

Nos. 9,836,885; 10,102,673; 10,510,111; and 10,592,973 states “the location of the viewpoint 

[was] still restricted to the location at which the panorama photo was taken.” Redfin denies all 

allegations of Paragraph 31 that it has not specifically admitted.

32. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 32, and on that basis, Redfin denies all allegations of Paragraph 32.

33. Redfin admits that the ‘885 patent has 18 claims, of which claims 1 and 10 are 

independent claims. Redfin denies all allegations of Paragraph 33 that it has not specifically 

admitted.

34. Redfin denies all allegations of Paragraph 34.

35. Redfin denies all allegations of Paragraph 35.

36. Redfin denies all allegations of Paragraph 36

37. Redfin denies all allegations of Paragraph 37.

38. Redfin denies all allegations of Paragraph 38.

39. Redfin denies all allegations of Paragraph 39.

40. Redfin denies all allegations of Paragraph 40.

41. Redfin denies all allegations of Paragraph 41.

42. Redfin admits that Paragraph 42 accurately quotes a portion of claim 1 of the ‘885 

patent. Redfin denies all allegations of Paragraph 42 that it has not specifically admitted.

43. Redfin admits that the ‘673 patent has 19 claims, of which claims 1, 10, and 13

are independent claims. Redfin denies all allegations of Paragraph 43 that it has not specifically 

admitted.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 5 of 13
6

44. Redfin admits that Paragraph 44 accurately quotes a portion of claim 1 of the ‘673 

patent. Redfin denies all allegations of Paragraph 44 that it has not specifically admitted.

45. Redfin admits that Paragraph 45 accurately quotes a portion of claim 1 of the ‘673 

patent. Redfin denies all allegations of Paragraph 45 that it has not specifically admitted.

46. Redfin admits that Paragraph 46 accurately quotes a portion of claim 1 of the ‘673 

patent. Redfin denies all allegations of Paragraph 46 that it has not specifically admitted.

47. Redfin admits that Paragraph 47 accurately quotes a portion of claim 1 of the ‘673 

patent. Redfin denies all allegations of Paragraph 47 that it has not specifically admitted.

48. Redfin admits that Paragraph 48 accurately quotes a portion of claim 1 of the ‘673 

patent. Redfin denies all allegations of Paragraph 48 that it has not specifically admitted.

49. Redfin denies all allegations of Paragraph 49.

50. Redfin denies all allegations of Paragraph 50.

51. Redfin denies all allegations of Paragraph 51.

52. Redfin admits that the ‘111 patent has 23 claims, of which claims 1 and 18 are 

independent claims. Redfin denies all allegations of Paragraph 52 that it has not specifically 

admitted.

53. Redfin admits that Paragraph 53 accurately quotes a portion of claim 1 of the ‘111 

patent. Redfin denies all allegations of Paragraph 53 that it has not specifically admitted.

54. Redfin admits that Paragraph 54 accurately quotes a portion of claim 1 of the ‘111 

patent. Redfin denies all allegations of Paragraph 54 that it has not specifically admitted.

55. Redfin admits that Paragraph 55 accurately quotes a portion of claim 1 of the ‘111 

patent. Redfin denies all allegations of Paragraph 55 that it has not specifically admitted.

56. Redfin denies all allegations of Paragraph 56.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 6 of 13
7

57. Redfin admits that Paragraph 57 accurately quotes a portion of claim 1 of the ‘111 

patent. Redfin denies all allegations of Paragraph 57 that it has not specifically admitted.

58. Redfin admits that the ‘973 patent has 23 claims, of which claims 1 and 18 are 

independent claims. Redfin denies all allegations of Paragraph 58 that it has not specifically 

admitted.

59. Redfin admits that Paragraph 59 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 59 that it has not specifically admitted.

60. Redfin admits that Paragraph 60 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 60 that it has not specifically admitted.

61. Redfin admits that Paragraph 61 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 61 that it has not specifically admitted.

62. Redfin admits that Paragraph 62 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 62 that it has not specifically admitted.

63. Redfin admits that Paragraph 63 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 63 that it has not specifically admitted.

64. Redfin admits that Paragraph 64 accurately quotes a portion of claim 1 of the ‘973 

patent. Redfin denies all allegations of Paragraph 64 that it has not specifically admitted.

65. Redfin denies all allegations of Paragraph 65.

66. Redfin denies all allegations of Paragraph 66.

D. Redfin’s [Alleged] Willful Infringement of the Patents-in-Suit

67. Redfin denies the allegations of Paragraph 67.

68. Redfin denies all allegations of Paragraph 68.

69. Redfin denies all allegations of Paragraph 69.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 7 of 13
8

70. Redfin is without sufficient information to admit or deny any allegation of 

Paragraph 70, and on that basis, Redfin denies all allegations of Paragraph 70.

71. Redfin denies all allegations of Paragraph 71.

72. Redfin admits that it received notice of the Patents-In-Suit as of service of the 

Complaint. Redfin denies all allegations of Paragraph 72 that it has not specifically admitted.

V. CAUSES OF ACTION

Cause of Action No. 1: [Alleged] Infringement of the ‘885 Patent by Redfin

73. Redfin admits and denies all allegations of Paragraphs 1 – 72 of the Complaint as 

it admitted or denied such allegations in Paragraphs 1 – 72.

74. Redfin denies all allegations of Paragraph 74.

75. Redfin denies all allegations of Paragraph 75.

76. Redfin denies all allegations of Paragraph 76.

77. Redfin denies all allegations of Paragraph 77.

78. Redfin denies all allegations of Paragraph 78.

Cause of Action No. 2: [Alleged] Infringement of the ‘673 Patent by Redfin

79. Redfin admits and denies all allegations of Paragraphs 1 – 78 of the Complaint as 

it admitted or denied such allegations in Paragraphs 1 – 78.

80. Redfin denies all allegations of Paragraph 80.

81. Redfin denies all allegations of Paragraph 81.

82. Redfin denies all allegations of Paragraph 82.

83. Redfin denies all allegations of Paragraph 83.

84. Redfin denies all allegations of Paragraph 84.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 8 of 13
9

Cause of Action No. 3: [Alleged] Infringement of the ‘111 Patent by Redfin

85. Redfin admits and denies all allegations of Paragraphs 1 – 84 of the Complaint as 

it admitted or denied such allegations in Paragraphs 1 – 84.

86. Redfin denies all allegations of Paragraph 86.

87. Redfin denies all allegations of Paragraph 87.

88. Redfin denies all allegations of Paragraph 88.

89. Redfin denies all allegations of Paragraph 89.

90. Redfin denies all allegations of Paragraph 90.

Cause of Action No. 4: [Alleged] Infringement of the ‘973 Patent by Redfin

91. Redfin admits and denies all allegations of Paragraphs 1 – 90 of the Complaint as 

it admitted or denied such allegations in Paragraphs 1 – 90.

92. Redfin denies all allegations of Paragraph 92.

93. Redfin denies all allegations of Paragraph 93.

94. Redfin denies all allegations of Paragraph 94.

95. Redfin denies all allegations of Paragraph 95.

96. Redfin denies all allegations of Paragraph 96.

VI. JURY DEMAND

97. Paragraph 97 does not contain an allegation requiring a response by Redfin.

VII. PRAYER FOR RELIEF

Redfin denies that Plaintiff is entitled to any relief in this action, including, but not 

limited to, any of the requested relief.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 9 of 13
10

AFFIRMATIVE DEFENSES

Non-Infringement

1. Redfin has not infringed any claim of U.S. Patent No. 9,836,885.

2. Redfin has not infringed any claim of U.S. Patent No. 10,102,673.

3. Redfin has not infringed any claim of U.S. Patent No. 10,510,111.

4. Redfin has not infringed any claim of U.S. Patent No. 10,592,973.

Invalidity

5. One or more claims of U.S. Patent No. 9,836,885 are invalid under one or more of 

35 U.S.C. sections 101, 102, or 103.

6. One or more claims of U.S. Patent No. 10,102,673 are invalid under one or more 

of 35 U.S.C. sections 101, 102, or 103.

7. One or more claims of U.S. Patent No. 10,510,111 are invalid under one or more 

of 35 U.S.C. sections 101, 102, or 103.

8. One or more claims of U.S. Patent No. 10,592,973 are invalid under one or more 

of 35 U.S.C. sections 101, 102, or 103.

9. One or more claims of U.S. Patent No. 9,836,885 are invalid under one or more of 

35 U.S.C. sections 112.

10. One or more claims of U.S. Patent No. 10,102,673 are invalid under one or more 

of 35 U.S.C. sections 112.

11. One or more claims of U.S. Patent No. 10,510,111 are invalid under one or more 

of 35 U.S.C. sections 112.

12. One or more claims of U.S. Patent No. 10,592,973 are invalid under one or more 

of 35 U.S.C. sections 112.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 10 of 13
11

Estoppel

13. Plaintiff’s legal claims are barred in whole or in part by the doctrine of estoppel. 

By way of example, and without limitation, Plaintiff is estopped under the doctrines of 

prosecution history estoppel and/or prosecution history disclaimer, due to amendments of the 

claims of the asserted patents and/or related patents and/or arguments presented to the patent 

examiner during examination of the applications that issued as the asserted patents and/or related 

patents, from (1) asserting any construction of the claims of the asserted patents such that they 

would read on any product, system, or method of Redfin, or (2) extending the coverage of the 

claims of the asserted patents under the doctrine of equivalents such that they would read upon 

any product, system, or method of Redfin.

PRAYER FOR RELIEF

WHEREFORE, Redfin prays for relief against Plaintiff as follows:

A. That the Court determine that Redfin has not infringed any claim of United States 

Patent Nos. 9,836,885; 10,102,673; 10,510,111; and 10,592,973.

B. That the Court determine that the claims of United States Patent Nos. 9,836,885; 

10,102,673; 10,510,111; and 10,592,973 are invalid under one or more of 35 U.S.C. sections 

101, 102, 103, 112.

C. Dismissal of the Complaint with prejudice.

D. An award to Redfin of its costs.

E. A finding that, pursuant to 35 U.S.C. § 285 and/or other applicable laws, 

Plaintiff’s conduct in commencing and pursuing this action renders this an exceptional case and 

an award to Redfin of its attorneys’ fees incurred in this action.

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 11 of 13
12

F. That Plaintiff take nothing by way of its complaint.

G. Such other and further relief granted to Redfin as the Court deems just and proper.

DEMAND FOR JURY TRIAL

In accordance with Rule 38 of the Federal Rules of Civil Procedure, Redfin respectfully 

demands a jury trial of all issues in this action triable to a jury.

Dated: June 25, 2020 Respectfully submitted,

 /s/ J. Thad Heartfield 

J. Thad Heartfield

State Bar No. 09346800

thad@heartfieldlawfirm.com

THE HEARTFIELD LAW FIRM

2195 Dowlen Road

Beaumont, TX 77706

Telephone: (409) 866-3318

Facsimile: (409) 866-5789

Michael F. Heafy

(Pro hac vice motion pending)

LAW OFFICES OF MICHAEL F. HEAFY

1325 Howard Avenue, Suite 160

Burlingame, CA 94010

Telephone: (650) 346-4161

Matthew H. Poppe

(Pro hac vice motion pending)

RIMON P.C.

800 Oak Grove Avenue, Suite 250

Menlo Park, CA 94025

Telephone: (650) 461-4433

Facsimile: (650) 461-4433

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 12 of 13
13

Benjamin J. Byer

(Pro hac vice motion pending)

DAVIS WRIGHT TREMAINE LLP

920 Fifth Avenue, Suite 3300

Seattle, WA 98104-1610

Telephone: (206) 757-8105

Facsimile: (206) 757-7105

Attorneys for Defendant

Redfin Corporation

CERTIFICATE OF SERVICE

The undersigned hereby certifies that on June 25, 2020, a true and correct copy of the 

foregoing document was caused to be served on all counsel of record who are deemed to have 

consented to electronic service via the Court’s CM/ECF system per Local Rule CV-5(b)(1).

Dated: June 25, 2020 /s/ J. Thad Heartfield

J. Thad Heartfield

Case 6:20-cv-00376-ADA Document 18 Filed 06/25/20 Page 13 of 13