HOUSTON, April 24, 2024 – Oceaneering International, Inc. ("Oceaneering") (NYSE:OII) today reported net income of $15.1 million, or $0.15 per share, on revenue of $599 million for the three months ended March 31, 2024. Adjusted net income was $13.9 million, or $0.14 per share, reflecting the positive impact of $(2.2) million in foreign exchange gains, and the associated $0.8 million of tax effects, along with $0.2 million of expenses related to discrete tax adjustments.

For the first quarter of 2024:

•Net income was $15.1 million and consolidated adjusted EBITDA was $61.7 million

•Consolidated operating income was $36.7 million

•Cash flow used in operating activities was $69.7 million and free cash flow was $(95.2) million, with an ending cash position of $355 million

As of March 31, 2024:

•Remotely Operated Vehicles (ROV): fleet count was 250; Q1 utilization was 64%; and Q1 average revenue per day on hire was $10,009

•Manufactured Products backlog was $597 million

Confirmed prior guidance for 2024:

•Net income is expected in the range of $125 million to $155 million

•Consolidated EBITDA is expected in the range of $330 million to $380 million

•Free cash flow generation is expected in the range of $110 million to $150 million

•Capital expenditures are expected in the range of $110 million to $130 million

Roderick A. Larson, President and Chief Executive Officer of Oceaneering, stated, "We are encouraged by our first quarter 2024 results. Our adjusted EBITDA was higher than guided, on better-than-expected activity levels across our businesses. Compared to the same quarter last year, our consolidated first quarter 2024 operating income was 37% higher on a 12% increase in revenue, with higher revenue in all of our business segments and improved operating income in each segment except for our Offshore Projects Group (OPG). These results, when combined with our backlog and current levels of bidding activity, support our unchanged guidance for the year." Subsea Robotics (SSR) first quarter 2024 operating income of $44.2 million was 31% higher than the first quarter of 2023.

EBITDA margin improved to 31%, as compared to the 29% margin achieved in the first quarter of 2023.

Average ROV revenue per day on hire of $10,009 was 9% higher, utilization improved to 64%, and days on hire increased 2% to 14,536. ROV fleet use during the quarter was 66% in drill support and 34% in vessel-based activity, compared to 65% and 35%, respectively, in the first quarter of the prior year.

Manufactured Products operating income improved 17% on a 15% increase in revenue compared to the first quarter of 2023, while operating income margin remained flat at 10%. Backlog was $597 million on March 31, 2024, an increase of $151 million compared to backlog on March 31, 2023. The book-to-bill ratio was 1.30 for the 12-month period ending March 31, 2024, as compared to the book-to-bill ratio of 1.27 for the same period last year.

OPG operating income declined as expected due to drydock expenses incurred during the first quarter of 2024, on an increase in revenue compared to the first quarter of 2023. Operating income margin declined to 1% in the first quarter, from 5% in the first quarter of 2023.

Integrity Management and Digital Solutions (IMDS) operating income improved year over year on a 16% increase in revenue. Operating income margin of 5% was flat.

Aerospace and Defense Technologies (ADTech) operating income increased by $4.3 million. Revenue increased 8% and operating income margin improved to 13% from 9% in the first quarter of 2023.

At the corporate level, Unallocated Expenses of $38 million were below guidance for the quarter but higher than the same period last year.

For the second quarter of 2024, as compared to the first quarter 2024:

•OPG activity levels and operating profitability are expected to be significantly higher;

•SSR and Manufactured Products activity levels and operating profitability are expected to be higher;

•IMDS and ADTech activity levels are expected to be flat and operating profitability is expected to be slightly lower; and

•Unallocated Expenses are forecasted to be in the $40 million range, consistent with prior guidance.

On a consolidated basis, second quarter 2024 operating results are expected to improve, with EBITDA in the range of $80 million to $90 million on a mid-teens percentage increase in revenue.

Full-year 2024 consolidated and segment guidance remains the same as provided in the fourth quarter 2023 earnings release, inclusive of the following clarification and addition:

•SSR revenue increase is expected to be in the low- to mid-teens percentage range; and

•Manufactured Products book-to-bill ratio is expected to be in the range of 1.1 to 1.3 for the full year.

Adjusted net income (loss) and earnings (loss) per share; EBITDA and adjusted EBITDA (as well as EBITDA and adjusted EBITDA margins); and free cash flow are non-GAAP measures that exclude the impacts of certain identified items. Reconciliations to the corresponding GAAP measures are shown in the tables Adjusted Net Income (Loss) and Diluted Earnings (Loss) per Share (EPS), EBITDA and Adjusted EBITDA and Margins, Free Cash Flow, 2024 Adjusted EBITDA and Free Cash Flow Estimates, and EBITDA and Adjusted EBITDA and Margins by Segment. These tables are included below under the caption Reconciliations of Non-GAAP to GAAP Financial Information.

Oceaneering has scheduled a conference call and webcast on Thursday, April 25, 2024 at 9:00 a.m. Central Time, to discuss its results for the first quarter of 2024, as well as more detailed

guidance for the full year and second quarter of 2024. Interested parties may listen to the call through a

webcast link posted in the Investor Relations section of Oceaneering's website. A replay of the

conference call will be made available on the website approximately two hours following the conclusion of the live call.

Oceaneering is a global technology company delivering engineered services and products and robotic solutions to the offshore energy, defense, aerospace, manufacturing, and entertainment industries.

For more information on Oceaneering, please visit www.oceaneering.com.

Contact:

investorrelations@oceaneering.com

Hilary Frisbie

Senior Director, Investor Relations

713-329-4755

Mark Peterson

Vice President, Corporate Development and Investor Relations

713-329-4507

- Tables follow on next page -

In addition to financial results determined in accordance with U.S. generally accepted accounting principles ("GAAP"), this Press Release also includes non-GAAP financial measures (as defined under certain rules and regulations promulgated by the Securities and Exchange Commission). We have included Adjusted Net Income (Loss) and Diluted Earnings (Loss) per Share, each of which excludes the effects of certain specified items, as set forth in the tables that follow. As a result, these amounts are non-GAAP financial measures. We believe these are useful measures for investors to review because they provide consistent measures of the underlying results of our ongoing business. Furthermore, our management uses these measures as measures of the performance of our operations. We have also included disclosures of Earnings Before Interest, Taxes, Depreciation and Amortization (EBITDA), EBITDA Margins, 2023 Adjusted EBITDA Estimates, and Free Cash Flow, as well as the following by segment: EBITDA, EBITDA Margins, Adjusted EBITDA and Adjusted EBITDA Margins. We define EBITDA Margin as EBITDA divided by revenue. Adjusted EBITDA and Adjusted EBITDA Margins and related information by segment exclude the effects of certain specified items, as set forth in the tables that follow. EBITDA and EBITDA Margins, Adjusted EBITDA and Adjusted EBITDA Margins, and related information by segment are each non-GAAP financial measures. We define Free Cash Flow as cash flow provided by operating activities less organic capital expenditures (i.e., purchases of property and equipment other than those in business acquisitions). We have included these disclosures in this press release because EBITDA, EBITDA Margins and Free Cash Flow are widely used by investors for valuation purposes and for comparing our financial performance with the performance of other companies in our industry, and the adjusted amounts thereof provide more consistent measures than the unadjusted amounts. Furthermore, our management uses these measures for purposes of evaluating our financial performance. Our presentation of EBITDA, EBITDA Margins and Free Cash Flow (and the Adjusted amounts thereof) may not be comparable to similarly titled measures other companies report. Non-GAAP financial measures should be viewed in addition to and not as substitutes for our reported operating results, cash flows or any other measure prepared and reported in accordance with GAAP. The tables that follow provide reconciliations of the non-GAAP measures used in this press release to the most directly comparable GAAP measures.

`