David L Houston

Insider

First SEC filing: Nov. 13, 2009 · Latest: Nov. 13, 2009

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Insider at

0 buys (P) 0 sells (S) Net: $0 + 15 non-open-market transactions below last 12 months, based on the transactions shown below

Price change vs current quote, split-adjusted for corporate actions since the filing — not benchmarked, not annualized, not size-weighted

15 other filings hidden

Date	Ticker	Code	Shares	Price	Value	Owned after	Δ own	A/D	vs now
June 6, 2019	GPOR	A	32,588	—	—	96,855 Direct	+50.71%	Acquired	(price as of 2026-08-20)
May 31, 2018	GPOR	A	11,201	—	—	64,267 Direct	+21.11%	Acquired	(price as of 2026-08-20)
June 8, 2017	GPOR	A	9,608	—	—	53,066 Direct	+22.11%	Acquired	(price as of 2026-08-20)
June 10, 2016	GPOR	A	3,824	—	—	43,458 Direct	+9.65%	Acquired	(price as of 2026-08-20)
Sept. 10, 2015	GPOR	A	3,830	—	—	39,634 Direct	+10.70%	Acquired	(price as of 2026-08-20)
Dec. 30, 2014	GPOR	M	10,000	—	—	0 Direct	-100.00%	Disposed	(price as of 2026-08-20)
Dec. 30, 2014	GPOR	M	10,000	$3.36	$33,600	35,804 Direct	+38.75%	Acquired	5060.7% (price as of 2026-08-20)
July 15, 2014	FANG	A	2,802	—	—	9,468 Direct	+42.03%	Acquired	(price as of 2026-08-20)
July 10, 2014	GPOR	A	1,609	—	—	25,804 Direct	+6.65%	Acquired	(price as of 2026-08-20)
May 15, 2014	GPOR	M	10,000	—	—	10,000 Direct	-50.00%	Disposed	(price as of 2026-08-20)
May 15, 2014	GPOR	M	10,000	$3.36	$33,600	24,195 Direct	+70.45%	Acquired	5060.7% (price as of 2026-08-20)
Dec. 10, 2013	GPOR	A	863	—	—	14,195 Direct	+6.47%	Acquired	(price as of 2026-08-20)
Nov. 5, 2012	GPOR	A	6,666	—	—	13,332 Direct	+100.00%	Acquired	(price as of 2026-08-20)
Oct. 11, 2012	FANG	A	6,666	—	—	6,666 Direct	—	Acquired	(price as of 2026-08-20)
Feb. 7, 2012	GPOR	S 10b5-1	20,000	$36.00	$720,000	6,666 Direct	-75.00%	Disposed	381.7% (price as of 2026-08-20)
Nov. 3, 2009	GPOR	A	6,666	—	—	16,666 Direct	+66.66%	Acquired	(price as of 2026-08-20)

P = Open-market purchase · S = Sale · A = Grant/award · M = Option exercise · G = Gift · F = Tax withholding

Insider transactions are not a recommendation; sales are often driven by liquidity or tax reasons.

Options, RSUs and convertible securities reported on Form 4 Table II.

Date	Ticker	Security	Underlying	Exercise price	Expiration	Shares	A/D
Dec. 30, 2014	GPOR	Non-Qualified Stock Option (right to buy)	Common Stock	$3.36	Jan. 24, 2015	10,000	Disposed
May 15, 2014	GPOR	Non-Qualified Stock Option (right to buy)	Common Stock	$3.36	Jan. 24, 2015	10,000	Disposed
Oct. 11, 2012	FANG	Restricted Stock Units [F1]	Common Stock (6,666)	—	—	6,666	Acquired

Exercise/conversion price is blank when not applicable (e.g. RSUs).