Oroco Resource Corp. (TSX-V: OCO) (OTCQB: ORRCF) is pleased to report the fifth batch of assay results from its Phase 2 resource drilling program in the South Zone of the Santo Tomás copper project in Choix, Sinaloa, Mexico. The assayed results cover ten drill holes, including S045 that delivered a 234.6-metre interval of 0.52% CuEq from an initial depth of 174.1 m. Drill-hole location data are shown in Table 1, with significant results referenced in Table 2.

Phase 2 has now completed 50 holes in the South and Pillar Zones, with 15,263.2 m drilled and three rigs operating at Santo Tomás. South Zone resource drilling is now complete, while Pillar Zone and geotechnical work continue. The Company has previously reported Phase 2 results through hole S044. Drill-hole locations are shown in Figure 1.

Highlights

• S045: 234.6 m at 0.43% Cu (0.52% CuEq) from 174.1 m, a broad central South Zone intercept.
• S046: 128.0 m at 0.36% Cu (0.48% CuEq) from surface, with additional mineralization below the 2024 Preliminary Economic Analysis (“PEA“) pit.
• S049: 86.1 m at 0.51% Cu (0.60% CuEq) from 85.5 m, reinforcing the southern higher-grade zone.
• S050: 6.0 m of carbonate-hosted mineralization at 4.18% Zn, 1.71% Pb, 75 g/t Ag, 0.35 g/t Au and 0.48% Cu from 36.0 m.
• S051: 102.3 m at 0.46% Cu from 35.0 m, beginning near the base of overburden on the western margin.
• S053: 84.2 m at 0.50% Cu (0.58% CuEq) from 159.6 m, confirming higher-grade mineralization in the south.
• S056: 95.4 m at 0.29% Cu (0.38% CuEq) from 40.6 m, shallower than modelled at the northwestern pit margin.

All intervals are downhole lengths; true widths remain to be confirmed. See Table 2 and the accompanying technical notes. No processing route is currently planned for the S050 carbonate-hosted mineralization.

“These results continue to strengthen our optimism for an expanded resource model at Santo Tomás together with increased certainty as to the grade continuity and overall project viability,” stated Oroco’s CEO, Charles Cryer. “With South Zone resource drilling now complete, we look forward to seeing how these very positive overall results influence the valuation presented in the project’s next economic assessment.”

Southern Quarter of the South Pit

Drill holes S046, S048, S049 and S053 were among the final holes in the southern quarter of the South Pit. Their results support the current PEA block model and the area of higher grades centred around S018 (Phase 1); assays for S054 remain pending. S046 also returned 26.0 m at 0.31% Cu (0.43% CuEq) from 351.0 m and 14.1 m at 0.23% Cu (0.30% CuEq) from 387.0 m, below the PEA pit. As reported in previous news releases, any potential addition to Mineral Resources in this area would be subject to updated geological and resource modelling, pit optimization, stripping constraints and the requirement for reasonable prospects of eventual economic extraction.

Western Edge of the South Pit

Drilling along the underexplored western extents of the block model and PEA pit design continued with S051 and S056. S051 results, in conjunction with Cu-Ox outcropping mineralization to the west of the hole, suggest the pit limit may extend in that direction. The higher-grade interval begins essentially at the base of overburden. This interval correlates well with historical drill hole STD-37 to the east. S056, a Pillar Zone hole north of previously reported S033 and S034, was drilled towards the ESE. Its mineralization reinforces the interpretation that the main mineralized horizon flattens to the west. This geometry may allow a shallower pit locally and lower stripping requirements, subject to updated resource modelling and mine planning. Visual observations in other western-margin holes are consistent with this interpretation, but assays remain pending for some of those holes.

North-Central Area of the South Pit and Eastern South Pit Limits

Drill hole S045 was collared in the central portion of the South Pit as an infill hole and supported the grades presented in the block model in that area. Hole S047 represents the eastern-most hole in the central portion of the south pit and confirmed the up-dip extension of weakening mineralization towards the east. It highlighted that historical drill hole STE-57 may have stopped short of the mineralized zone at depth. Further drilling is warranted to the north and east. A planned geotechnical hole will cover the area to the south.

Northeastern Low-Grade and Waste Area of the South Pit

Drill holes S050 and S055 were collared in the northeastern quadrant of the South Pit. Both returned sporadic lower-grade copper assays, consistent with the block model. S050 also intersected carbonate-hosted zinc-lead-silver mineralization immediately above the andesite contact: 6.0 m from 36.0 m returned 0.48% Cu, 4.18% Zn, 1.71% Pb, 75 ppm Ag and 0.35 ppm Au, including 2.0 m at 0.76% Cu, 6.4% Zn, 2.20% Pb, 130 ppm Ag and 0.47 ppm Au. The low reported sulphur grade of 0.18% suggests a non-sulphide component; mineralogical confirmation is required. S055, 100 m north of S050, exhibited anomalous Zn and Pb around the same geological contact, at much lower grades and with higher sulphur values. S066, a Pillar Zone hole 120 m NNW of S055, intersected visually identified copper mineralization; assays are pending. Visual observations do not establish grade or economic viability.

Table 1. Drill-hole locations and purpose.

Assays for S052, S052A and S054 remain in QA/QC for re-assay and review.

Table 2: Significant Copper Assay Intercepts**

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* CuEq (%) = [(Cu% × Cu recovery (variable) × Cu price) + (Mo% × Mo recovery (variable) × Mo price) + (Au g/t × Au recovery (variable) × Au price) + (Ag g/t × Ag recovery (variable) × Ag price)] ÷ (Cu price × Cu recovery (variable)). Metal prices are stated in US$/lb for Cu and Mo and US$/oz for Au and Ag; see Table 3. Metal recoveries are grade-based for each assay within the reported intervals and vary accordingly. Across these intervals, Cu recovery ranges from 82% to 89%, Mo from 50% to 60%, Au from 30% to 85% and Ag from 35% to 67%. Au and Ag recoveries depend on copper and sulphur grades. Copper-equivalent grades are not reported for intervals containing both sulphide and non-sulphide copper. The CuEq presented in Figure 1 is calculated using the method described above.

** Significant intervals are at least 10 m long and comprise samples that grade at least 0.15% Cu, but may include individual intervals of up to 4 m grading at least 0.05% Cu. Where a hole contains multiple assay intervals in reasonable downhole proximity, lower-grade intervals are also reported to show continuity with significant intercepts and are not themselves held out as significant. This is consistent with the significant-interval reporting convention used for Phase 1 news releases and the August 2024 PEA. Copper-equivalent grades are not reported for intervals with copper oxide assays. The shorter, carbonate-hosted interval in S050 is described separately above and does not meet the 10 m minimum length used for this table.

CuT is total copper, determined by ALS method ME-ICP61 using a four-acid digest.

CuSol is soluble copper, determined by ALS method Cu-AA05 using a sulphuric-acid leach on intervals exhibiting oxidation. Soluble-copper assays are included for S051 in this release and have been reported for relevant holes previously.

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

Figure 1: Phase 2 drill holes S045 to S056 in relation to prior drilling and completed Phase 2 holes awaiting assays. Results for S052, S052A and S054 remain pending.

Phase 2 Program and Project Context Update

Phase 2 is designed primarily to provide the drilling density and technical data needed to evaluate the potential conversion of Inferred Mineral Resources to the Indicated category in the South Zone. The program is also collecting geotechnical, hydrogeological and metallurgical data to support pre-feasibility study (“PFS”)-level mine planning.

The South Zone resource-drilling component is complete, with drilling continuing in the Pillar Zone between the North and South Zones. Geotechnical drilling has commenced. Where feasible, the geotechnical holes will serve as resource infill drilling. Drill holes S067 (423 m) and S068 (438 m) were recently completed, while GT003 is in progress at 80 m in the South Zone. To date, 12,830.1 m of core has been sampled during Phase 2, through hole S063, representing 8,512 samples: 7,063 core samples and 1,449 QA/QC samples.

Additional Updates

Mexico permitting momentum: ProMinería, citing figures supplied by Mexico’s Ministry of Economy to BNamericas, reported that approximately 84% of the 185 mining environmental applications tracked jointly with SEMARNAT had been resolved by June 30, 2026. Separately, Southern Copper confirmed in July that its El Pilar open-pit copper project in Sonora had obtained the necessary environmental permits, and Discovery Mining Ltd. announced receipt of permits for their large open pit Cordero silver project (October 5, 2026). Oroco regards these events as compelling evidence that Mexico has normalized the permitting and advancement of large mining projects.

Vainilla geophysics program in preparation: Following completion of a 707 line-kilometre drone magnetic survey over ~3,114 hectares, the Company is designing a follow-up 3D DCIP geophysics program over priority areas at the Vainilla property, which is located approximately 17 km south of the Santo Tomás South Zone.

Copper Equivalent (CuEq) Reporting

CuEq grades in this release are calculated using the variable metal-recovery curves in Chapter 13 of the Company’s August 2024 technical report, “Santo Tomás Copper Project, Sinaloa, Mexico – Technical Report on a Preliminary Economic Assessment” (the “PEA”), filed on SEDAR+ in August 2024, and the metal-price deck in Table 3, which reflects 12-month trailing average prices to April 30, 2026. This price deck differs from the one used in the PEA.

The CuEq grades in this release are therefore not directly comparable with CuEq grades reported in the Company’s 2024 Indicated and Inferred Mineral Resource summary or in drill-result news releases issued before 2024, which used different metal-price assumptions and/or CuEq methodologies. The Company has recalculated the significant-intercept database for the full drill-hole dataset using the updated CuEq methodology. Historical drilling results and results for holes S022 through S044 have been updated in the VRIFY drill-hole viewer and are available through VRIFY and the Company’s website. CuEq values are not calculated for intervals with soluble-copper assays (please refer to News Release of August 6, 2026 and this release).

Table 3: Metal Prices Used for Phase 2 CuEq Calculations

Quality Assurance / Quality Control

Both the historical drilling data used in the current exploration program and Mineral Resource Estimate and the Phase 2 drilling data reported in this news release were subject to the data-verification procedures described in the Company’s current technical report. Drill-collar locations are verified by differential GPS and checked against LiDAR data. Geological logging, core sampling, sample preparation, analysis, and chain of custody are governed by QA/QC protocols that include certified reference materials, blanks and duplicates. Samples are prepared by ALS Chemex in Hermosillo, Mexico, and pulps are sent to ALS Canada Ltd. in Vancouver for analysis. Total copper, molybdenum, and silver are determined by ALS method ME-ICP61 (four-acid ICP-AES). Over-limit copper (>10,000ppm) is re-assayed using Cu-OG62, soluble copper is determined by Cu-AA05, and gold is determined by Au-AA23 (30 g fire assay with an AAS finish). Over limit Ag (>100 ppm), Zn (>10,000 ppm) and Pb (>10,000 ppm) are determined by ALS using analytical techniques Ag-OG62, Zn-OG62 and Pb-OG62 respectively.

Qualified Person

Andrew Ware, RM-SME, a Qualified Person as defined by National Instrument 43-101 – Standards of Disclosure for Mineral Projects and a senior consulting geoscientist to the Company, has reviewed and approved the scientific and technical information in this news release. The Company follows CIM Best Practices Guidelines in conducting, documenting and reporting its 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 the surrounding concessions. Historical drilling between 1968 and 1994, together with Oroco’s Phase 1 program of 48,481 m in 76 diamond drill holes, supported the revised Mineral Resource Estimate and updated PEA.

Santo Tomás is included among the strategic investment projects under Plan México and has been recognized as the primary mining development within the Topolobampo Economic Hub, with federal and state support for permitting. Santo Tomás is the only mining project included in Plan México.

The August 2024 MRE, prepared by SRK Consulting (U.S.), Inc., outlined an Indicated Resource of 540.6 Mt at 0.33% Cu, 0.008% Mo, 0.028 ppm Au and 2.1 ppm Ag and an Inferred Resource of 530.3 Mt at 0.31% Cu, 0.007% Mo, 0.023 ppm Au and 1.9 ppm Ag. The updated PEA, prepared by Ausenco Engineering USA South Inc., contemplates a staged, open-pit operation ramping from 60,000 t/d in Year 1 to 120,000 t/d by Year 8 over 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%. Both studies are available at www.orocoresourcecorp.com and on SEDAR+ at www.sedarplus.ca. The PEA is preliminary in nature; 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.