SEC Insider Transactions from Mao Robert Yu Lang.

Last updated: 2026-03-14 10:18 UTC | Total transactions: 30

Mao Robert Yu Lang has filed 30 insider transactions across 1 company since February 2024.

Most recent transaction: a option exercise of 21859 shares of Energy Recovery, Inc. ($ERII) on May 22, 2024.

Activity breakdown: 0 open-market purchases and 6 sales.

Set Up your own filters →
Transaction Date Company Ticker Insider Name Title Transaction Type Security Shares Price Shares Owned Following Total Shares Outstanding % of Owned % of Outstanding
May 22, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 21859 $7.79 348,144.0000 65,029,459 6.70% 0.03%
May 22, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 5208 $7.79 353,352.0000 65,029,459 1.50% 0.01%
May 22, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 21045 $13.86 332,307.0000 65,029,459 5.96% 0.03%
May 23, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 10752 $7.79 343,059.0000 65,029,459 3.24% 0.02%
May 23, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 2084 $7.79 345,143.0000 65,029,459 0.61% 0.00%
May 22, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Employee Stock Option (Right to Buy) 21859 $7.79 10,752.0000 65,029,459 67.03% 0.03%
May 22, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Employee Stock Option (Right to Buy) 5208 $7.79 2,084.0000 65,029,459 71.42% 0.01%
May 23, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Employee Stock Option (Right to Buy) 10752 $7.79 0.0000 65,029,459 100.00% 0.02%
May 23, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Employee Stock Option (Right to Buy) 2084 $7.79 0.0000 65,029,459 100.00% 0.00%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 20509 $2.92 292,829.0000 65,029,459 7.53% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 20509 $15.74 272,320.0000 65,029,459 7.00% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 15327 $8.60 287,647.0000 65,029,459 5.63% 0.02%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 15270 $15.74 272,377.0000 65,029,459 5.31% 0.02%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 16726 $7.71 289,103.0000 65,029,459 6.14% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 15879 $8.49 304,982.0000 65,029,459 5.49% 0.02%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 21303 $9.98 326,285.0000 65,029,459 6.99% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 20509 $0.00 0.0000 65,029,459 100.00% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 16726 $0.00 0.0000 65,029,459 100.00% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 15879 $0.00 0.0000 65,029,459 100.00% 0.02%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 21303 $0.00 0.0000 65,029,459 100.00% 0.03%
March 4, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 15327 $0.00 0.0000 65,029,459 100.00% 0.02%
Feb. 29, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 39314 $3.53 311,634.0000 65,029,459 14.44% 0.06%
Feb. 29, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 39314 $15.58 272,320.0000 65,029,459 12.62% 0.06%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 5142 $3.53 277,462.0000 65,029,459 1.89% 0.01%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Common Stock 32883 $2.92 310,345.0000 65,029,459 11.85% 0.05%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 5142 $16.22 305,203.0000 65,029,459 1.66% 0.01%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director S Common Stock 32883 $16.21 272,320.0000 65,029,459 10.77% 0.05%
Feb. 29, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 39314 $0.00 5,142.0000 65,029,459 88.43% 0.06%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 5142 $0.00 0.0000 65,029,459 100.00% 0.01%
March 1, 2024 Energy Recovery, Inc. $ERII Mao Robert Yu Lang Director M Stock Option (Right to Buy) 32883 $0.00 20,509.0000 65,029,459 61.59% 0.05%