证券代码：300321 证券简称：同大股份 公告编号：2025-053 山东同大海岛新材料股份有限公司 关于召开 2025 年第二次临时股东会的通知 本公司及董事会全体成员保证信息披露的内容真实、准确、完整，没有虚假记载、误导性陈述或 重大遗漏。 一、召开会议的基本情况 1、股东会届次：2025 年第二次临时股东会 2、股东会的召集人：董事会 3、本次会议的召集、召开符合《中华人民共和国公司法》《深圳证券交易所创业板股 票上市规则》《深圳证券交易所上市公司自律监管指引第 2 号—创业板上市公司规范运作》 等法律、行政法规、部门规章、规范性文件及《公司章程》的有关规定。 4、会议时间： （1）现场会议时间：2025 年 12 月 24 日 14:00 （2）网络投票时间：通过深圳证券交易所系统进行网络投票的具体时间为 2025 年 12 月 24 日 9:15-9:25，9:30-11:30，13:00-15:00；通过深圳证券交易所互联网投票系统投 票的具体时间为 2025 年 12 月 24 日 9:15 至 15:00 的任意时间。 5、会议的召开方式：现场表决与网络投票相结合。 6、会议的股权登记日：2 ...

证券代码：300321 证券简称：同大股份 公告编号：2025-051 山东同大海岛新材料股份有限公司 第六届董事会第十五次会议决议公告 本公司及董事会全体成员保证信息披露的内容真实、准确、完整，没有虚假记载、 误导性陈述或重大遗漏。 山东同大海岛新材料股份有限公司（以下简称"公司"）第六届董事会第十 五次会议于 2025 年 12 月 8 日在公司会议室以现场方式召开，会议通知以书面及 电子邮件方式于 2025 年 12 月 5 日发出。会议应到董事 9 人，实到董事 9 人，公 司高管列席了会议。本次会议由董事长寇相东先生主持，会议的召集、召开程序 符合《公司法》及《公司章程》的相关规定。 经与会董事讨论审议，本次会议形成如下决议： 本议案需提交公司 2025 年第二次临时股东会审议。 具体内容详见公司同日在巨潮资讯网（www.cninfo.com.cn）披露的《关于 拟变更会计师事务所的公告》。 四、审议通过《关于召开 2025 年第二次临时股东会的议案》 公司定于 2025 年 12 月 24 日下午 14：00 时在公司会议室召开 2025 年第二 次临时股东会。 表决情况：同意 9 票，反对 0 ...

Core Viewpoint - The company, Tongda Co., Ltd. (300321), has stated that it will fulfill its information disclosure obligations in accordance with relevant laws and regulations [1] Group 1 - The company responded to investor inquiries on an interactive platform [1]

Market Performance - The Shandong state-owned enterprise reform sector rose by 0.63% compared to the previous trading day, with Yaxing Chemical leading the gains [1] - The Shanghai Composite Index closed at 3888.6, up 0.34%, while the Shenzhen Component Index closed at 12984.08, up 0.85% [1] Top Gainers - Yaxing Chemical (600319) closed at 9.75, up 10.05% with a trading volume of 348,200 shares and a transaction value of 330 million yuan [1] - Tongda Co., Ltd. (300321) closed at 50.65, up 6.01% with a trading volume of 32,800 shares and a transaction value of 162 million yuan [1] - Zhongda An (300635) closed at 18.61, up 5.50% with a trading volume of 83,600 shares and a transaction value of 153 million yuan [1] Top Losers - Chuirich Co., Ltd. (002083) closed at 10.17, down 5.31% with a trading volume of 1,710,100 shares and a transaction value of 1.743 billion yuan [2] - Xinhua Pharmaceutical (000756) closed at 17.57, down 2.77% with a trading volume of 375,600 shares and a transaction value of 660 million yuan [2] - Aokema (600336) closed at 7.74, down 2.15% with a trading volume of 301,500 shares and a transaction value of 231 million yuan [2] Capital Flow - The Shandong state-owned enterprise reform sector experienced a net outflow of 270 million yuan from institutional investors, while retail investors saw a net outflow of 137 million yuan [2] - Speculative funds had a net inflow of 408 million yuan into the sector [2] Individual Stock Capital Flow - Shandong Gold (600547) had a net outflow of 96.17 million yuan from institutional investors, while speculative funds saw a net inflow of 20.34 million yuan [3] - Yaxing Chemical (600319) experienced a net inflow of 56.99 million yuan from institutional investors, but a net outflow of 21.75 million yuan from speculative funds [3] - Shandong Steel (600022) had a net inflow of 29.74 million yuan from institutional investors, with a net outflow of 9.31 million yuan from speculative funds [3]

Group 1 - The core point of the article is that Tongda Co., Ltd. (300321) experienced a stock price decline of 4.04% on November 21, 2025, closing at 45.85 yuan, with a total market capitalization of 4.071 billion yuan [1] - The stock opened at 47.75 yuan, reached a high of 48.0 yuan, and a low of 45.55 yuan, with a trading volume of 74.0555 million yuan and a turnover rate of 1.79% [1] - A major shareholder, Huasheng Baili Investment Development (Beijing) Co., Ltd., reduced its stake by 887,000 shares, representing 1% of the total share capital, decreasing its holding from 9.96% to 8.96% [1] - The reduction occurred between August and November 2025, and the plan was executed in accordance with the pre-disclosure scheme without violating any laws or regulations [1] - The reduction was conducted solely through centralized bidding transactions, with no block trades executed, and did not result in a change of the controlling shareholder or actual controller of the company [1]

Core Points - The company announced that its major shareholder, Huasheng Baili Investment Development (Beijing) Co., Ltd., plans to reduce its stake by up to 2,664,000 shares through centralized bidding and block trading [2] - The reduction includes a maximum of 888,000 shares (1% of total share capital) through centralized bidding and 1,776,000 shares (2% of total share capital) through block trading [2] - As of the announcement date, Huasheng Baili has reduced its holdings by 887,000 shares, bringing its ownership down from 9.96% to 8.96% [2] Company Actions - The company received a notification from Huasheng Baili regarding the completion of its reduction plan, which has not exceeded the agreed number of shares [2] - The reduction plan was executed within the stipulated time frame, with the total number of shares reduced touching the 1% integer multiple [2]

Core Viewpoint - The company Tongda Co., Ltd. (300321.SZ) has received a notification from Huasheng Baili regarding a reduction in shareholding, indicating a significant change in ownership structure [1] Group 1: Shareholding Changes - Huasheng Baili has reduced its shareholding in Tongda Co., Ltd. by 887,000 shares, which accounts for 1% of the company's total share capital [1] - Following the reduction, Huasheng Baili's ownership percentage decreased from 9.96% to 8.96% [1] - The reduction in shareholding has reached the 1% integer threshold, and the planned reduction period has expired [1]

证券代码：300321 证券简称：同大股份 公告编号：2025-049 山东同大海岛新材料股份有限公司 关于 5%股东权益变动触及 1%整数倍暨减持计划时间届满的公告 本公司及董事会全体成员保证信息披露的内容真实、准确和完整，没有虚 假记载、误导性陈述或重大遗漏。 山东同大海岛新材料股份有限公司（以下简称"公司"）于 2025 年 7 月 31 日在巨潮资讯网披露了《关于持股 5%以上股东及董事减持股份的预披露公告》 （公告编号：2025-009），公司持股 5%以上股东华盛百利投资发展（北京）有 限公司（以下简称"华盛百利"）计划以集中竞价及大宗交易方式减持不超过 2,664,000 股公司股份。其中，在任意连续 90 日内通过交易所集中竞价交易减 持不超过公司总股本的 1%，即 888,000 股；在任意连续 90 日内通过大宗交易减 持不超过公司总股本的 2%，即 1,776,000 股。 一、权益变动触及 1%整数倍的情况说明 今日，公司收到华盛百利出具的《关于权益变动触及 1%整数倍暨减持计划 时间届满的告知函》，华盛百利已通过集中竞价方式累计减持公司股份 88.7 万 股，占公司总股本的 1%，减 ...

关于使用闲置自有资金购买国债逆回购和理财产品的进展公告 本公司及董事会全体成员保证信息披露的内容真实、准确、完整，没有虚假记 载、误导性陈述或重大遗漏。 证券代码：300321 证券简称：同大股份 公告编号：2025-050 山东同大海岛新材料股份有限公司 山东同大海岛新材料股份有限公司（以下简称"公司"）于 2025 年 9 月 26 日召开的第六届董事会第十三次会议、第六届监事会第十二次会议审议通过了 《关于使用闲置自有资金购买国债逆回购和理财产品的议案》，同意公司使用不 超过人民币 1 亿元的闲置自有资金购买国债逆回购和安全性高、流动性好的低风 险类理财产品，在上述额度内，资金可以滚动使用，授权期限为公司董事会审议 通过本议案之日起 12 个月内有效。具体内容详见公司于 2025 年 9 月 26 日在巨 潮资讯网披露的《第六届董事会第十三次会议决议公告》、《第六届监事会第十 二次会议决议公告》及《关于使用闲置自有资金购买国债逆回购和理财产品的公 告》。 一、使用闲置自有资金购买国债逆回购和理财产品的基本情况 1、2025 年 11 月 21 日，公司使用闲置自有资金人民币 4,000 万元购买了上 海 ...

Group 1 - The stock price of Tongda Co., Ltd. (300321) closed at 47.12 yuan on November 12, 2025, with a slight increase of 0.26% and a turnover rate of 1.82% [1][2] - On November 12, 2025, the net outflow of main funds was 744.37 million yuan, while speculative and retail funds saw net inflows of 500.33 million yuan and 244.04 million yuan, respectively [1][2] Group 2 - On October 15, 2025, Tongda Co., Ltd. used 80 million yuan of idle self-owned funds to purchase government bond reverse repos on the Shanghai Stock Exchange, with the total amount divided into three transactions of 60 million yuan, 10 million yuan, and 10 million yuan, yielding annualized rates of 1.50%, 1.505%, and 1.51% respectively [1][2] - The investments matured on November 12, 2025, and the principal and interest were fully recovered, with the company establishing internal management systems to ensure fund safety [1][2]