Oroco Resource Corp. (TSX-V: OCO) (OTCQB: ORRCF) is pleased to report the initial assay results from its Phase 2 resource drilling program focused on the South Zone at its Santo Tomás copper project, Choix, Sinaloa, Mexico. Results are available for drill holes S022, S023, and S024.

Highlights:

• S022: 228.55 m at 0.38% Cu / 0.49% CuEq, including 64.86 m at 0.53% Cu / 0.69% CuEq
• S023: 212.33 m at 0.34% Cu / 0.44% CuEq, including multiple sub-intervals of ≥0.50 Cu / ≥0.61% CuEq, plus 31.76 m at 0.50% CuEq from near-surface
• Holes S022 and S023, drilled from the same pad as Phase 1 hole S018, further confirm a higher-grade area of South Zone mineralization
• S022 and S023 also returned elevated molybdenum grades in deeper intervals, increasing CuEq values at depth and indicating a higher-grade core that will be tested by four additional holes planned south and east of the S018/S022/S023 pad
• S024 intersected intermittent mineralization at the western resource margin and confirms the current Inferred resource boundary estimated in the 2024 PEA block model
• Phase 2 program to date: 3,606 m drilled in 14 holes; 3 holes with reportable assays (this release) and 4 holes at the assay laboratory

“These initial Phase 2 results provide increased grade and validation of the Company’s development plan for Santo Tomás,” said Craig Dalziel, Executive Chairman. “The program is focused on increasing the confidence level in the South Zone resource to that required for mine planning and the completion of a positive Pre-Feasibility Study. The elevated grades returned from holes S022 and S023 are particularly encouraging, and the Company will continue testing this area of the South Zone.”

Phase 2 Program Overview

Phase 2 is designed primarily to convert Inferred resources to Indicated classification in the South Zone and to collect geotechnical, hydrogeological, and metallurgical data required for Pre-Feasibility Study level mine planning. Drilling is also planned in the pillar area between the North and South Zones and along the southeastern edge of the North Zone pit shell. The PFS is targeted for release in Q2/Q3 2027.

Table 1: Phase 2 Drill Hole Locations, Objectives and Comments

Table 2: Significant Assay Results — Phase 2 Holes S022–S024

*CuEq (%) = [(Cu% × Cu recovery × Cu price) + (Mo% × Mo recovery × Mo price) + (Au g/t × Au recovery × Au price) + (Ag g/t × Ag recovery × Ag price)] ÷ (Cu price × Cu recovery). Metal prices in US$/lb (Cu, Mo) and US$/oz (Au, Ag) See table 3

All intervals are drill core lengths. True widths will be confirmed when Phase 2 results are incorporated into the updated geological and resource models. Where holes are drilled approximately perpendicular to the interpreted structural attitude of the mineralization, core intervals are expected to approximate true thickness.

† S024 was drilled to define the extent of mineralization at the western resource margin and is not perpendicular to the mineralization. Intervals for S024 do not reflect true width.

Copper Equivalent Reporting

CuEq grades in this release are calculated using the variable metal recovery curves from Chapter 13 of the Company’s August 2024 Technical Report and the metal price deck in Table 3, reflecting 12-month trailing average prices to April 30, 2026.

Copper equivalent grades in this release are not directly comparable to CuEq grades reported in the Company’s 2024 Indicated and Inferred Resource Summary Table or in earlier drill-result news releases, which used different metal price assumptions and CuEq methodologies. The Company intends to recalculate the significant-intercept database for the full drill-hole dataset using the updated CuEq calculation and make those results available on the Company’s website in due course.

Table 3: Metal Prices Used for Phase 2 CuEq Calculations

Quality Assurance / Quality Control

Historical drilling data used in the current exploration program were subject to the data verification procedures described in the Company’s current Technical Report. Drill collar locations are verified by differential GPS with checks against LiDAR data. Geological logging, core sampling, sample preparation, analysis, and chain of custody are governed by QA/QC protocols that include the insertion of certified reference standards, blanks, and duplicates. Samples are submitted to ALS Chemex (Hermosillo, Mexico) for sample preparation; pulps are sent to ALS Canada Ltd. (Vancouver) for analysis. Total copper, molybdenum, and silver are determined by ALS method ME-ICP61 (four-acid ICP-AES); over-limit results use ore-grade assay methods. Gold is determined by ALS method Au-AA23 (30 g fire assay with AAS finish).

Qualified Person

Andrew Ware, RM-SME, a Qualified Person as defined in NI 43-101 — Standards of Disclosure for Mineral Projects, and a senior consulting geoscientist to the Company, has reviewed and approved the technical disclosures in this news release. The Company adheres to CIM Best Practices Guidelines in conducting, documenting, and reporting exploration activities.

About Santo Tomás

Santo Tomás is an advanced-stage porphyry copper project in Choix, Sinaloa, Mexico. Oroco holds a net 88.5% interest in the 1,173-hectare Core Concessions and an 80% interest in surrounding concessions at Santo Tomás. The Project was tested by historical drilling from 1968 to 1994 and by Oroco’s Phase 1 program, which totaled 48,481 metres in 76 diamond drill holes and supported the revised Mineral Resource Estimate and updated Preliminary Economic Assessment filed in August 2024.

The August 2024 MRE, prepared by SRK Consulting (U.S.), Inc., outlined an Indicated Resource of 540.6 Mt and an Inferred Resource of 530.3 Mt across the North and South Zones. The PEA, while preliminary in nature, was prepared by Ausenco Engineering USA South Inc., and contemplates a staged open-pit operation ramping from 60,000 t/d in Year 1 to 120,000 t/d by Year 8 within a 22.6-year life of mine, generating an after-tax NPV₈% of US$1.48 billion and an after-tax IRR of 22.2%. The study, based on US$4.00 Cu/lb, is available at www.orocoresourcecorp.com and on SEDAR+ at www.sedarplus.ca. See “Cautionary Note” below.

About Oroco Resource Corp.

Oroco Resource Corp. is a Vancouver-based mineral exploration and development company advancing the Santo Tomás copper project in Sinaloa, Mexico.

For further information:

Christy Fabros
info@orocoresourcecorp.com
(604) 688-6200