Final Report on the Website Disruption (Notice of Full Service Restoration)

Worth reading

48Recurring

Scored from 4 of 5 sections

Direction

Neutral

Direction inferred from the company’s description.

Scale

—

Displayed only when the document provides numerical figures.

Wording

Definitive

How definitive the wording is.

Subject Entity

IBIDEN CO.,LTD.

Target Locations / Products

Our website

OccurrenceAround 7:30 a.m. on Monday, 13 April 2026

Same day

Awareness or receipt of notice13 April 2026, when we became aware of the incident affecting our website

This disclosure04/28/2026

Cause

Unauthorized access to an external web server

Company response

Suspended operations

Temporarily suspended access to our website

Scheduled resumption date

Full restoration of the website was completed on 28 April 2026.

Investigation structure

An internal investigation and analysis were conducted. We are using a web server environment whose security was verified by a new third-party organization.

Measures to prevent recurrence

Ongoing strengthening of system security

Amount of Impact on Business Performance

This incident had no impact on our financial results.

Outlook

We will operate the website in a web server environment whose security was verified by a new third-party organization, continue strengthening system security, and work to ensure the website's security and stable operation and restore trust.

Event that occurred
Item	Details
Event name	Final Report on the Website Disruption (Notice of Full Service Restoration)
Date of occurrence	Around 7:30 a.m. on Monday, 13 April 2026
Date recognized / date notice received	13 April 2026, when we became aware of the incident affecting our website
Subject Entity	IBIDEN CO.,LTD.
Target Locations / Products	Our website
Cause	Unauthorized access to an external web server
Amount of Impact on Business Performance	This incident had no impact on our financial results.
Suspended operations	Temporarily suspended access to our website
Scheduled resumption date	Full restoration of the website was completed on 28 April 2026.
Investigation structure	An internal investigation and analysis were conducted. We are using a web server environment whose security was verified by a new third-party organization.
Measures to prevent recurrence	Ongoing strengthening of system security
Outlook	We will operate the website in a web server environment whose security was verified by a new third-party organization, continue strengthening system security, and work to ensure the website's security and stable operation and restore trust.

Items this document does not state (13)

Accounting period in which recognizedImpact on Earnings ForecastType of litigation or proceedingCourt or authorityPlaintiffDefendantDate of filing / date of actionClaim amount / surcharge amountAmount of receivables at risk of non-collection or delayed collectionDirectors' and officers' liabilityVoting rights ownership percentage before the changeVoting rights ownership percentage after the changePlanned follow-up disclosure

These are items the company does not state in this document. We do not leave them blank, nor fill them in from other sources or by inference.

The reasons the company gives

The company's own explanation, not something inferred from the numbers.

We have determined that the incident was caused by unauthorized access to an external web server.

How to read this page

This is not the documentKomori reads the disclosure the company filed and writes this summary. Figures are as stated by the company and are not audited.

Weight is not a verdictIt measures how much this changes what the company had already told the market. It is not a view on the shares.

Corrections happenIf the company reissues this disclosure, the page is rebuilt from the corrected version and the revision number moves up.