The Securities and Exchange Commission has not necessarily reviewed the information in this filing and has not determined if it is accurate and complete.
The reader should not assume that the information is accurate and complete.

UNITED STATES SECURITIES AND EXCHANGE COMMISSION
Washington, D.C. 20549
FORM 13F

FORM 13F INFORMATION TABLE
OMB APPROVAL
OMB Number: 3235-0006
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COLUMN 1 COLUMN 2 COLUMN 3 COLUMN 4 COLUMN 5 COLUMN 6 COLUMN 7 COLUMN 8
VALUE SHRS OR SH/ PUT/ INVESTMENT OTHER VOTING AUTHORITY
NAME OF ISSUER TITLE OF CLASS CUSIP (x$1000) PRN AMT PRN CALL DISCRETION MANAGER SOLE SHARED NONE
Aspen Aerogels, Inc. Common 04523Y105 24,578 3,167,322 SH   SOLE n/a 3,167,322 0 0
BOK Financial Corp Common 05561Q201 253,189 2,896,899 SH   SOLE n/a 2,896,899 0 0
Boston Omaha Corp - CL A Common 101044105 3,999 190,059 SH   OTR n/a 190,059 0 49,127
Alphabet Inc. - CL C Common 02079K107 2,282 1,707 SH   OTR n/a 0 0 1,707
Analog Devices, Inc. Common 032654105 1,028 8,647 SH   OTR n/a 0 0 8,647
Berkshire Hathaway Inc. - CL B Common 084670702 3,747 16,543 SH   OTR n/a 0 0 16,543
Comcast Corp - CL A Common 20030N101 1,613 35,875 SH   OTR n/a 0 0 35,875
Costco Wholesale Corp Common 22160K105 1,303 4,434 SH   OTR n/a 0 0 4,434
Facebook, Inc. - CL A Common 30303M102 1,631 7,946 SH   OTR n/a 0 0 7,946
JPMorgan Chase & Co. Common 46625H100 4,887 35,056 SH   OTR n/a 0 0 35,056
Liberty Broadband Corp - Series C Common 530307305 4,597 36,557 SH   OTR n/a 0 0 36,557
Liberty Media Corp Series C Sirius XM Group Common 531229607 1,735 36,034 SH   OTR n/a 0 0 36,034
Microsoft Corp Common 594918104 3,553 22,533 SH   OTR n/a 0 0 22,533
Mohawk Industries, Inc. Common 608190104 1,883 13,809 SH   OTR n/a 0 0 13,809
Moodys Corp Common 615369105 1,872 7,887 SH   OTR n/a 0 0 7,887
PayPal Holdings, Inc. Common 70450Y103 804 7,432 SH   OTR n/a 0 0 7,432
Qurate Retail, Inc. - Series A Common 74915M100 1,288 152,769 SH   OTR n/a 0 0 152,769
Ryanair Holdings PLC Common 783513203 2,628 29,998 SH   OTR n/a 0 0 29,998
S&P Global Inc. Common 78409V104 2,081 7,623 SH   OTR n/a 0 0 7,623
SAP SE Common 803054204 1,200 8,954 SH   OTR n/a 0 0 8,954
Telefonaktiebolaget LM Ericsson - Series B Common 294821608 1,402 159,632 SH   OTR n/a 0 0 159,632
TripAdvisor, Inc. Common 896945201 578 19,023 SH   OTR n/a 0 0 19,023
Voxx International Corp - CL A Common 91829F104 1,554 354,740 SH   OTR n/a 0 0 354,740
Wells Fargo & Co Common 949746101 1,889 35,113 SH   OTR n/a 0 0 35,113